The anatomy of the human body

*m

T H E

ANATOMY

OF THE

HUMAN BODY.

By WILLIAM GHESELDEN,

SURGEON TO HIS MAJESTY'S ROYAL HOSPITAL AT CHELSEA, FELLOW,

OF THE ROYAL SOCIETY, AND MEMBER OF THE ROYAL

ACADEMY OF SURGEONS AT PARIS.

rritfi Srortu CsohherfolatM.

jFttfl American etutton.

■ i

BOSTON:

PRINTED BY MANNING & LORING,

For J. WHITE, S. HALL, THOMAS # ANDREWS, D. WEST,

W. SPOTSWOOD, E. LARKIN, J. WEST,

and the PROPRIETOR of

the Bcjion Bcoijiurc.

*795-

Dr. RICHARD MEAD,

PHYSICIAN to the KING,

FELLOW OF THE

COLLEGE of PHYSICIANS

IN LONDON,

AND OF THE

ROYAL SOCIETY.

SIR,

*

EVERY part of PHYSIC may juftly pre-
fume en your protection, to whom it owes fo
much improvement. ANATOMY in par-
ticular has received fuch advantage from your
Lectures, that it were a kind of injuftice not
to dedicate all endeavours in that way to you ;
in mc, indeed, it would be unpardonable not to
offer the fruits of thofe ftudies, which at firft be-
A 2 gan.

DEDICATION.

gan, and have ftill been carried on with your
encouragement. The kind reception my induftry
has met with, is owing to you, the authority of
whofe opinion has in every place fecured me fo
much favour ; efpecially in that feat of learning,
which with diftinguiihed honours rewarded your
merit.

/ am, S IR y

Tour mqfi obliged and
Obedient humble fervant.

William Cheselden.

PREFACE.

j[ HE fudy of Anatomy, as it leads to the
knowledge of nature and the art of healing, needs
not many tedious defcriptions nor minute diffeclions \
what is mofl worth knowing, is foonefl learned, and
leaf the fubjefl of difputes ; while dividing and
defcribing the parts, more than the knowledge of
their ufes requires, perplexes the learner, and makes
the fcience dry and difficult.

This edition is a tenth part larger than the
former ; not increafed by defcriptions, but by obfer-
vations upon the ufes and mechanifn of the parts,
with operations and cafes in Surgery.

The plates are more in number, larger, better
defgned, and better executed than thofe which were
in the former editions, which has unavoidably en-
hanced the price of this.

CONTENTS.

CONTENTS,

BOOK I.

ZlHE General Introduction Page I

Introduction to the Bones 4

Chap. I. Of the Sutures and Bones of the Cranium 1 1
Chap. II. Of the Bones of the Face, &V. 17

Chap. III. Of the Bones of the Trunk 11

Chap. IV. Of the Bones of the Upper Limbs 29
Chap. V. Of the Boms of the Lower Limbs 34
Chap. VI. Of the Cartilages 41

Of the Ligaments 44

Of the Lubricating Glands of the

Joints 47

BOOK II.

Chap. I. Introduction to the Mufcles 61

Chap. II. Of the Mufcles 67

BOOK III.

Chap. I. Of the External Parts, and Common

Integuments 133

Chap. II. Of the Membranes in general 141

Chap. III. Of the Salivary Glands 142

Chap. IV. Of the Peritoneum, Omentum, Duc-
tus Aliment alis, and Mefentcry 148

Chap.

CONTENTS. v

Chap. V. Of the Liver ; Gall-Bladder, Pancreas,

and Spleen Page 1 6 1

Chap. VI. Of the Vafa La&ea 168
Chap. VII. Of the Pleura, Mediafinum, Lungs,

Pericardium and Heart 172

Chap. VIII. Of the Arteries and Veins 183

Chap. X. Of the Lymphce duels 209

Chap. XI. Of the Lymphatic Glands 212
Chap. XII. Of the Courfe of the Aliment ab-

Jlradted from the foregoing Chapters 216
Chap. XIII. Of the Dura Mater, and Pia

Mater 2 1 8
Chap. XIV. Of the Cerebrum, Cerebellum, Me-
dulla Oblongata, and Medulla Spinalis 222
Chap. XV. Of the Nerves 225

, B O O K IV.

Chap. I. Of the Urinary and Genital Paris
of Men, together ivith the Glandula

.Renales 259

Chap. II. Of the Genital Parts of Women 272

Chap. III. Of the Fa?tus in Utcro 278

Chap. IV. Of the Eye 290

Chap. V. Of the Ear 304
Chap. VI. Of the Senfes of Smelling, Tqft'mg

and Feeling 3 l °

Chap. VII. Of Cutting for the Stone 325

ADVERTISEMENT.

SlNCE the laft Edition of this Book, I have pub-
lifhed fome Obfervations and Cafes in Surgery,
with Prints of Operations and a Set of Chirurgical
Inftruments. Thefe are annexed to a Tranflation
of Le Dran's Operations by Mr. Gataker;
and as fome of them relate to my Anatomy, I
thought it proper to take Notice of them here: At
the fame Time, in Juftice to the Merit of Mr. Le
Dran, I would recommend a careful Perufal of
his Book to all Pra&itioners in Surgery.

W. CHESELDEN.

THE

ANATOMY

OF THE

HUMAN BODY.

GENERAL INTRODUCTION.

IT is a received opinion, that an animal body-
is a compages of veflels, varioufly difpofed, to
form parts of different figures, for different ufes.
The ancients fuppofed that the heart and brain
were firft formed, and that the other parts pro-
ceeded from them, and that the membranes were
derived from the dura mater, or pia mater of
the brain. They diftinguifhed all the parts into
fpermatic and fanguineous ; the former of which
they derived from the brain, and the latter from
the heart ; and frequently engaged in difputes
about the derivation of parts ; with many other
things of the like nature, confequences of their
hypothefes. But the moderns, by the aflift-

ance

2 GENERAL INTRODUCTION.

ance of glaffes, having made more accurate obfer-
vations, conclude, that all the parts exift irl minia-
ture, from the firft formation of the fcetus ; and
that their increafe is only the extenfion and thick-
ning cf their veffels, and that no part owes its ex-
igence to another. Thus much I thought nec-
eflary to premife, that the reader might fee for
what reafon no notice is taken, in this treatife, of
fome diftinclions and divifions of parts, ufed by-
ancient anatomifts, and thofe who have copied
after them.

The constituent parts of the animal body, arc,
fibres, membranes, arteries, veins, lymphse duels,
nerves, glands, excretory veffels, mufcles, tendons,
ligaments, cartilages, and bones ; to thefe may be
added, the hair and nails.

Fibres, as they appear to the naked eye, are
fnnple threads of the minutefl blood veffels or
nerves, or both.

Membranes are compages of fibres, expanded
to cover, or line, any other part.

Arteries -are tubes that arife from the ventri-
cles of the heart, and thence dividing into branches,
diftribute the blood to every part of the body.

Veins are tubes to collect and return the blood
from the extremities of the arteries to the heart.

Lymphsedu&s.are fine pellucid tubes, to carry
lymph from all parts, efpecially the glands, which
they difcharge into the larger veins, and into the
vafa lactca.

Nerves

GENERAL INTRODUCTION. 3

Nerves are fafciculi of cylindrical fibres,
which arife from the medulla oblongata of the
brain, and the medulla fpinalis, and terminate in all
the fenfitive parts. They are the immediate organs
of fenfation.

A Gland fecretory, is compofed of an artery,
vein, lymphatic, excretory duel:, and nerve. The
ufe of glands is to fecrete fluids from the blcod, for
divers ufes.

Excretory veffels are either tubes fro
glands to convey the fecreted fluids to their refpec-
tive places ; or veffels from the fmall guts, to carry
the chyle to the blood veflels ; thefe lait are called
vafa la£tea.

Mufcles are diftin£t portions of flefh, which bv
contracting, perform the motions of the body.

Tendons are the fame fibres of which the muf-
cles are compofed ; but more clofely connected,
that they may poffefs lefs fpace in a limb, and be
inferted in lefs room into a bone.

Ligaments are flrong membranes, or bodies of
fibres clofely united, either to bind down the .
tendons, or give origin to the mufcles, or tie to-
gether fuch bones as have motion.

Cartilages are hard, elaftic bodies, fmooth and .
infenfible : their ufe is to cover the ends of the
bones that have motion, to prevent their attn
tion, &c.

Bones are firm parts to fuftain, and give fhape
to the body, &c.

INTRODUCTION

INTRODUCTION

TO THE

BONE

1HE ufe of the bones is to give fliape and
firmnefs to the body, to be levers for the muf-
cles to act upon, and to defend thofe parts from
external injuries that are of greateft confequence
to be preferved ; as the brain, fpinal marrow,
heart, &c. Their fibres, when firft formed like
the {hells and ftones of fruits, are very foft, un-
til by the addition of a matter, which is fecreted
into them, they grow by degrees to the hardnefs
of a cartilage, and then perfect bone : But this
change is neither made in a very fhort time, nor
begun in all the parts of the fame bone at once.
Flat bones, that have their fibres directed to all fides,
begin to offify in or near a middle point ; but the
cylindrical bones, and all others whofe fibres are
nearly parallel, begin about the middle of each
fibre, and thence fhoot forth to their extremities ;
not always in continued lines, but frequently begin-
ning new oflifications, which foon join the former ;
Wid by the continual addition of this offifying mat-
the bones increafe till their hardnefs refills a far-
ther extenfion ; and their hardnefs always increas-
ing while they are growing, the increafe of their
growth becomes flower and flower, until they ceafe

to

INTRODUCTION, &c. 5

to grow at all. In old and confumptive perfons,
and fometimes in difeafed or wounded limbs, they
decreafe as well as the flefhy parts, though not fo
faft, becaufe of their hardnefs. Sometimes the of-
fifying matters flows out of the bones, and forms
bony excrefcences ; and frequently in very old men
it fixes on the arteries, and makes them grow bony ;
and when this happens to a degree, the arte-
ries lofe their power to propel the blood, until the
extreme parts mortify. And though the cartilages
and arteries are moft fubjecl; to thefe changes, yet
no part is fecure from them ; for I have feen a
large part of the mufcular fibres of the heart itfelf
perfectly offified. I have known one inftance of
a deficiency of this oflifying matter, in the lower
jaw of an adult body ; where all that part on one
fide, which is beyond the teeth, was of a fubftance
between that of a cartilage and a ligament. In chil-
dren that have died of the rickets, I have found
the nodes on the bones foft, - fpongy, and bloody,
and in one fubject feveral of them as limber as
leather, and the perioftaeum in fome places many
times its natural thicknefs ; but the cartilages and
cartilaginous epiphyfes had no apparent alteration
in their texture, though fome were fwelled to
more than twice their natural diameters.

Every cylindrical bone has a large middle
cavity, which contains an oily marrow, and a
great number of lefTer cells towards their ex-
tremities, which contain a bloody marrow. The

bloodv

6 INTRODUCTION

bloody marrow is alfo found in all Spongy cells or
bones. The life of the firft kind of marrow, I
imagine, is to foften, and render lefs brittle, the
harder fibres of bones near which it is feated ;
and that the other marrow is of the fame ufe to
the lefs compact fibres, which the more oily mar-
row might have made too foft ; and that for this
reafon there is lefs of the oily marrow, and more
of the bloody, in young bones than in old ones.
Every one of thefe cells is lined with a fine mem-
brane, and the marrow in the larger cells is alfo
contained in thin membraneous veficles ; in which
membranes the veflels are fpread, which enter
obliquely, about the middle of the cylindrical
bones, from fome of whofe branches the marrow
is fecretcd, while others of them enter the internal
fubftance of the bones for their nourifhment ; and
the reafon why they enter obliquely is, that they
may not weaken the bones by dividing too many
fibres in the fame place. If the bones had been
formed of the fame quantity of matter without any -
cavities, they would, if they were ftraight, be able
to fuitain the fame weight : But being made hollow,
their ftrength to reiift breaking tranfverfely is in-
creafed as much as their diameters are increafed,
without encreafing their weights ; which mechan-
ifm being yet more convenient for birds, the bones
of their wings, and for the fame reafon their quills,
have very large cavities. But the bones in the legs
of all animals are more folid, being formed to fup-

port

to the BONES. 7

port weight ; and men's bodies being fupported by
two limbs, the bones of thofe limbs are therefore
made more folid than thofe of quadrupeds. In-
fects, and mod of the fmalleft animals, have fhelis
inftead of bones, like lobfters, which ferve them alio
for defence ; and the mufcles, being inferred into
the fhelis at a greater diftance from the centre of
motion of each joint than in animals that hayc
bones, their motions are neceilariiy flower, ftronger
and more fimple. Therefore in this fort of animals,
quicknefs of motion, where it is wanted, is pro-
cured by a number of joints, as may be feen in the
legs of a flea ; and variety of motions by joints
with different directions, as may be obferved in a
lobfter. In a fractured bone, in which the fame
kind of matter that oihfied the bones at firft is
thrown out from the broken ends of a bone, there
is formed a mafs of callous matter, of equal folid-
ity with any part of the bone, and of equal or
greater diameter, which will make the ftrength
of the bone in that place greater than it was be-
fore ; which is very convenient ; for bones, when
broke, are feldom or never fet in fo good a direc-
tion as that in which they were firft formed, and
therefore they would be more liable to be broke
in the fame place again, and would be reunited
with greater difficulty, and fometimes not at all,
becaufe the callus, being lefs vafcular than a bone,
it does not fo eafily admit the offific matter to now
through it to form a new callus.

Bonc^

B INTRODUCTION

Bones that are without motion, as thofe of the
fcull, the ofTa innominata, &c. alfo bones with
their epiphyfes, when they meet, prefs into each
other, and form futures, which foon difappear in
thofe that join, while their offific matter is foft ;
but thofe that grow harder before they meet, prefs
more rudely into each other, and make more un-
even futures, fome of which in the fcull endure to
the greateft age : and fometimes while a bone is
offifying from its centre, a diftant part begins a new
offification, and forms a diftincl: bone, which may
happen to be of any figure. Thefe bones are often-
eft found in the lambdoital future, and are there
called offa triquetra. But the ends or fides of bones
that are intended for motion, are hindered from
uniting, by the cartilages which cover them ; for
when thefe cartilages are eroded, the bones very
readily unite, and form an ancylofis.

The ends of all the bones that are articulated
for very manifeft motions, or that are not placed
againft other bones ; are tipped with epiphyfes or
additional bones ; which in fome meafure de-
termine their growth and figure ; for if they had
nothing to give bounds to them, they would fhoot
out like the callus from the broken ends of a bone
that is ill fet, and grow as ragged as the edges of
bones which are joined by futures ; and fometimes
epiphyfes are made ufe of to raife procefTes upon
bones for the infertions of mufcles, as the trochan-
ters of the thigh bones, where it would weaken

the

to the BONES. 9

the bones too much to have procefTes railed out of
their fubftance.

The fibres of bones, for aught that we can dif-
cover from experiments or microfcopical obferva-
tions, appear to be connected to each other by the
fame means that the parts of a fibre are connected,
that is, by the ftrong attraction which belongs to
particles of matter in contact ; but this cohefion
of fibre to fibre is not equal to that in the parts of
a fibre, though very nearly. Indeed if it was, a
bone would not be a ftructure of fibres, but one
uniform mafs, like that of any pure metal, the co-
hefion of the parts of which are every where alike.
Nor are the parts of bones difpofed into vifible la-
mellae, ftratum fuper ftratum, as many have paint-
ed : for though young bones may in fome places
be fplit into lamellae, yet they not only appear one
folid uniform mafs to the naked eye, but even with
a microfcope, till we come to their inner fpongy
texture, which alfo appears uniform. Their tex-
ture, when firft formed, is every where loofe and
spongy : but as they increafe, they become in ma-
ny places very compact and denfe, which refults in
great meafure from the prefTure of the bellies of
the mufcles, and other incumbent parts ; as ap-
pears from the impreflions they make on the fur-
faces of the bones, and the rough fpines that rife
on the bones in the interftices of the mufcles, which
are very remarkable in men who have been bred
up in hard labour. In thofe parts of the flat bones
B that

lo INTRODUCTION, &c.

that receive but little preffure, the outer lamina?
only become compact and denfe, while the mid-
dle part remains fpongy ; but where the preflure
is greater, as on the fcapula and the middle of
the ilium, they become, in an adult, one denfe •
body or table, and are ufually thinner in thofe
places than in a child before it is born. The cy-
lindrical or round bones, being preffed molt in
their middles, become there very hard and ftrong,
while their extremities remain fpongy, and dilate .
into large heads, which make flronger joints, and
give more room for the origins and infertions of
the mufcles ; and increafe the power of the muf- .
cles, by removing their axis farther from the
centre of motion of any joint they move.

All the bones, except, fo much of the teeth
as are out of the fockets, and thofe parts of other
bones which are covered with cartilages, or •
where mufcles or ligaments arife or are inferted,
are covered with a fine membrane, which upon
the fcull is called pericranium, elfewhere peri-
oftazum. It ferves for the mufcles to Aide eafy
upon, and to hinder them from being lacerated by •
the roughnefs and hardnefs of the bones. It is
every where full of fmall blood vefTels, which en-
ter the bones for their nouriihment ; but the in-
ternal fubftance of the larger bones is nourifhed
by the veffels which enter obliquely through
their middles, as has been before obferved.

CHAPTER

II

CHAPTER I.

Sutures and Bones of the Cranium.

A SUTURE i9 made by the mutual indenta-
tion of one tone with another. Thofe which
have proper names are here defcribed ; thofe
which have not, derive their names from the
bones they furround, and are known by them.

Sutura coronalis runs acrofs the fcull, from one
upper edge of the fphenoidal bone to the other,
and joins the parietal bones to the frontal.

Sutura fagittalis joins the parietal bones ; be-
gins at the os occipitis, and is continued to the os
frontis, in children down to the nofe ; the os fron-
ds in them being two bones, and fometimes fo in
adult bodies.

Sutura lambdoidalis joins the back part of the
ofTa bregmatis, or parietal bones, to the upper part
of the occipital : in this future are frequently ob-
ferved fmall bones called ofTa triquetra, and fome-
times in other futures.

Sutura fquamofa is made by the upper part of
the temporal and fpenoidal bones wrapping over
the lower edges of the parietal bones.

Sutura tranfverfalis runs acrofs the face through
the bottoms of the orbits of the eyes ; it joins the
lower edge of the frontal bone to t le os fpenoides,
maxillae fuperioris, ofTa nafi, ungues plana, pala-
ti, and jugalia, or malarum.

B 2 The

12

SUTURES and BONES

The fcull being divided into many bones, is
neither fo fubject to fractures, nor to have fractures
fo far extended, as it would have been were*it
compofed of one bone only. This ftructure is alfo
convenient for the omfication % of the bones, as has
been already mewn, and for the birth ; becaufe
thefe bones not being perfect at that time, may
be prefled together, and make the head lefs.

Ten of the bones of the head compofe the
cranium, to contain the brain and defend it from
external injuries.

Offa parietalia, or bregmatis are two large
bones which compofe the fuperior and lateral parts
of the fcull ; on the infide they are remarkably
imprinted by the arteries of the dura mater.:

Os frontis makes the upper and fore part of the
cranium ; its lower parts compofe the upper parts
of the orbits of the eyes, where on its infides are
impreifed the volvuli of the brain, which uneven-
neffes help to keep that part of the brain fteady.;
In its middle above the os ethmoides ufually arifes
a thin fpine, which ftrengthens that part of the
bone, it being otherwife weak from its flatnefs. In'
fome fculls this fpine is wanting ; but then the
bone is ufually "bicker in that place, and from its
middle, extei ly, goes a procefs which fupports
the bones of I nofe. Immediately above the os
ethmoides in t bone is a fmall blind hole, through
which runs a 1 into the beginning of the longi-
tudinal finus ( ie dura mater j and on the upper

edge

of the CRANI UM. 13

edge of each orbit, a fmall perforation, or a notch,
through which nerves and an artery pafs fecure to
the forehead ; it has alfo a fmall hole in each orbit,
near the os planum, through which paffes a branch
of the fifth pair of nerves. In the fubftance of
this bone near the nofe are two, three, four, and
fcmetimes five finufes, which open into the nofe j
they differ very much in different perfons, and are
very rarely found in children. Thefe finufes, and
the fpine in this bone, make it very dangerous, if
not impracticable, to apply a trephine on the mid-
dle and lower part of the forehead.

Os efthmoides, or cribriforme, is a fmall
bone, about two inches in circumference, feated in
the anterior part of the bafis of the fcull, being al-
moft furrounded by the laft defcribed bone.; It is
full of holes, like a fieve, through which, it is faid,
the olfactory nerves pafs, which I could never dif-
cover. In its middle arifes a large procefs named
crifta galli : and oppofite to this a thin one which
in part divides the nofe. The greater part of the
lamina? fpongiofse in the nofe belong to this bone.

Os fphenoides is of a very irregular figure ; it
is feated in the middle. of the bafis of the fcull,
bounded by the os frontis, ethmoides, vomer, occi-
pitis, maxillse fuperioris, offa parietalia, palati, ma-
larum, temporum, and pctrofa, which are parts of
tjie former bones.; In its infide next the brain is a
cavity named fella turcica, which is bounded by four
prccelfes called clinoides : under the two foremofl

of

r4 SUTURES and BONES

of which pafs the internal carotid arteries, and from
their outfides are continued two thin long proceffes
upon that part of the frontal bone, which feparates
the anterior lobes of the brain from the poflerior ;
oppofite to the fella turcica is a procefs which makes
part of the feptum narium. On the outfide of the
fcull adjoining to the upper jaw, are two proceffes
of this bone on each fide, named pterygoides from
which arife one on each fide near the palate, which
have no name. Over thefe pafs the tendons of the
pterygoflaphilina externi mufcles ; and nearer to-
wards the occiput, between thefe and the ftyloid
proceffes of the offa petrofa, arife two more fmall
rugged proceffes ; and under the fella turcica, in
this bone, is a fmus or two, for the moft part, in
adults, but in children only fuch a fpongy fubftance
as is feen in the ends of fome of the bones. Dr.
Nichols obferves, this finus belongs properly to
the os ethmoides. At the infide of the bafis of the
two anterior clinoid proceffes are two round holes,
which are the firft foramina of the fcull ; through
thefe the optic nerves pafs ; almoft under thefe, to-
wards the fides of the fcull, are two irregular flits,
named foramina lacera, or the fecond foramina of
the fcull, through which pafs nerves and blood
veffels into the orbits of the eyes ; and under thefe,
towards the occiput, are two round holes, which are
the third foramina, through which pafs nerves to
the face ; about half an inch nearer the occiput are
two more, of an are, which are the fourth

foramina,

jr

o* the CRANIUM. 15

foramina, through which pafs the largeft branches
of the fifth pair of nerves ; and a ftraw's breadth
farther two very fmall ones, called the fifth fora-
mina, through which thofe branches of the carotid
arteries enter that are bellowed upon the dura
mater. Between this laft defcribed bone and the
ofTa petrcfa are two large rough holes, in which
I have feen large veins ; and from thefe holes,
through part of the os fphenoides under the pte-
rygoid proceffes, are fmall holes, through which
pafs arteries to the back part of the nofe.

OfTa temporum are fituated below the parie-
tal bones, at the middle and lower parts of the fides
of the fcull ; they have each at their back parts
one large fpongy procefs, called mammillafis, or
maftoideus, and from the lower and middle parts
of each a procefs which joins the ofTa malarum,
named jugalis or zygomaticus. \

OfTa petrofa lie between the former bones
and the occipital bones, or are truly portions of the
former bones, being never found feparate in adult
bodies. ; They have each on their outfides one long
(lender procefs called flyliformis, and near the fide
of this procefs a foramen, which runs obliquely
forwards into the fcull, through which the carotid
arteries pafs to the brain ; thefe are the lixth fora-
mina, and one foramen in the infide of the fcull
leading to the organs of hearing, which are the fev-
enth foramina. The ridge on the upper parts of
each of thefe bones helps to keep the brain fleady,

and

16 SUTURES and BONES

and are ftrong fupports to the thin and flat parts
of the fcull, which elfe would be exceeding weak.
What remains of this bone belongs properly to a
difcourfe on the organs of hearing.

Between the laft defcribed bones and the fol-
lowing bone are two large holes, which are the
eighth foramina. Through thefe holes pafs the
eighth pair of nerves and lateral finufes ; fome-
times they are two on each fide, one for the nerve
and one for the finus. To thefe we may add an-
other very fmall one on each fide, through which
pafs the portiones durae of the auditory nerves j
and fometimes there is another for an artery.

Os occipitis makes all the back, part of the
fcull : it is bounded by the fphenoidal, temporal,
petrofal, and parietal bones ; it has two fmali
apophyfes, by which it is articulated to the fpine ;
near thofe apophyfes are two fmall foramina,
which are the ninth of the fcull ; through thefe
pafs the ninth pair of nerves ; and between thefe
is the great or tenth foramen, through which the
medulla oblongata defcends into the fpine, the cer-
vical arteries enter, and the cervical veins pafs out.>
In the infide of this bone is a crucial fpine im-
preffed by the longitudinal and lateral finufes :
and on the outfide, oppofite to the middle of this
fpine, in fome bodies, is an apophyfis, and from
that down to the great foramen a fmall thin fpine.
The fpines in this bone are of the fame ufe with
thofe in the cs frontis, &c. viz. to ftrengthen it.

The

of the CRANIUM. 17

The thinner parts of this bone are alfo defended by
the mufcles that cover them ; which provifion is
very neceffary, becaufe we can leaft defend this
part, and blows here are of worfe confequence than
on any other part of the fcull, becaufe wounds in
the cerebellum, which is underneath, are mortal.
There are in molt fculls a foramen behind each
apophyfis of the occipital bone ; through which
pafs fmufes from the lateral fmufes to the external
cervical veins : By means of thefe communications,
as in all other communications of the fmufes, the
blood paffes from thofe that happen to be fur-
charged by any pofture of the head, into thofe
that from 'the fame pofture would have been al-
moft empty. Such fculls as want thefe foramina
have two fmufes for the fame purpofe.

CHAP. II.

Of the Bones of the Face, &fc.

OSSA nafi make the upper part of the nofe ;
they form that kind of arch which is fitteft to fuf-
tain fuch injuries as the nofe is moft expofed to.,-
OfTa malarum. Thefe bones compofe the an-
terior, lower, and outer parts of the orbits of the
eyes ; they have each a fhort procefs, which pro-
ofs joins the procerus jugales of the temporal

bones,

i8 Of the BONES

bones, and form arches which have been called
offa jugalia.^

OfTa ungues are feated immediately below the
os frontis towards the nofe in the orbits of the
eyes ; whofe anterior and inner parts they help
to compole ; and between each of them and the
upper jaw is a foramin as large as a goofe quill, in-
to which the puncta lacrymalia lead, to carry off any
fuperfluous moifture from the eyes into the nofe.;
OfTa plana are feated immediately beyond the
foregoing bones, in the orbits of the eyes, and
are near thrice as big. 3 They are rather imooth
furfaces cf the os fpongioflim, than diftind bones,
and are very often imperfect.

Maxiila fuperior is always defcribed fingle,
though it is manifeftly divided by a future which
is fcarce ever obliterated ; it has two procefles,
which join the os frontis, and make part of the
nofe ; and another, which joins to the cartilage of
the feptum nafi. : Its upper and outward parts make
the lower parts of the orbits of the eyes ; its lower
fide, all that part of the face under the cheeks,
eyes, and nofe to the mouth, and two thirds of the
roof of the mouth. A little below the orbits of the .
eyes, in this bone, are two holes, and behind the
dentes inciibres one more, which divides into two,
as it opens into the nefc, on each fide of the fep-
tum nali. Between the poiTerior grinding-teeth
and the orbits of the eyes are two great iimifes,
called antra maxilla: fbperioris, which open in the

upper

of the FACE. 19

upper part of the nofe. And in the lower edge of
this jaw are the alveoli, or fockets for the teeth.
Part of the fides of thefe cavities, that lie next the
nofe, are only membranes which make the cavities
like drums, perhaps to give a grave found to the
voice when we let part of it through the nofe ;
but brutes not needing fuch variety of founds, have
thefe cavities open to the nofe, and filled with la-
mella?, which are covered with membranes, in
which the olfactory nerves terminate, for a more
exquifite fenfe of fmelling than is neceffary for
men. Impofthumations fometimes happen in
thefe cavities : The figns of this difeafe are, great
pain about the part, matter in the nofe on the fide
difeafed, ftinking breath, and rotten teeth. Mr.
Cowper nrft defcribed this cafe, and the cure ;
which is performed by drawing out the laft tooth
but one, or two, or more if rotten ; and through
their fockets making a perforation, into the antrum ;
or if drawing a tooth makes a perforation, which
fometimes happens, and perhaps gave the nrft hint
of this cure, then that opening muft be enlarged,
if it is not fufEcient to difcharge the matter.

Offa Palati are two fmall bones that make
the back part of the roof of the mouth, and a fmall
part of the bottom of each orbit.; Between the o$u
palati and os maxillare near the pterygoid proceffes
of the fphenoidal bone, are two fmall foramina,
through which arteries and nerves pafs to the pal-

Qs

20 Of the BONES

Os Vomer is feated between the bones of the
palate, and the fphenoidal bone. It is alfo joined to
the prccefs of the ethmoides, and part of the loW-'
er jaw. ; Its fpre part is fpongy, and is continued
to the middle cartilage of the nofe. This bone
and cartilage are the feptum nafi.

Os fpongiofum is ufually treated as a diftincl:
bone, though it is only the fpongy laminse in the
nofe, of the os ethmoides and offa plana, but chiefly
of the os ethmoides, to which it always adheres.;
In confidering thefe lamellae as a diftinc~t bone, we
follow the ancients, who did not diftinguifh the
bones of the fcull only, as they are divided by fu-
tures, but according to the differences of their tex-
ture, figure, fituation, or ufe. Thus they called
thefe parts os fpongiofum ; a procefs of the tempo-
ral bone, joined to the os malse, os jugale, &c.

Maxilla inferior is articulated with loofe car-
tilages to the temporal bones, by two proceffes,
named condyloides. Near thefe arife two more,
called coronales, and at the infide of the chin a
fmall rough proceffus innominatus. ; In the infide
of this bone, under each proceffus coronalis, is a
large foramin, which runs under the teeth, and
paffes out near the chin. In this foramen, the vef-
fels pafs that belong to the teeth ; and in the upper
edge of this jaw are the fockets for the teeth, which
feldom exceed fixteen in each jaw ; the four firft
in each are called incifores, the two next canini,
the reft molares ; the four Jaft of thefe are namecj

dentea

or the FACE. 21

dentes fapientiae, becaufe they do not appear till
men arrive at years of difcretion. The incifores and
canini have only one fingle root, but the molares
more ; the eight lirft, two ; and the reft, fome three,
fome four, efpecially in the upper jaw ; where alfo
they are fpread wider, becaufe that jaw being more
fpongy than the other, the teeth need more fpace
to fix them. Each of thefe roots has a foramen,
through which pafs an artery, vein, and nerve,
which are expanded in a fine membrane that lines
the cavity in each tooth. Thefe velfels and mem-
brane are the feat of the tooth-ache. The teeth of
children caft off while they are growing ; but the
fucceeding teeth arife in new fockets, deeper and
larger than the former, for the jaws increafing falt-
er than the teeth, muft otherwife have left chafms
between them, fuch as are in the mouths of brutes ;
but where teeth are drawn in adult bodies, the
fockets clofe, and new ones very rarely fucceed.

CHAP. III.
Of the Bones of the Trunk.

' 1 HE bones of the trunk are thofe which com-
pofe the fpine or chain of bones from the head
down to the rump, the ribs and fternum, to which
may jufdy be added the ofia innominata. ;

* The fpine is compofed of twenty-four vertebrae
(each of which in a young child is three bones)

befides

22 Of the BONES

befides thofe of the os facrum and coccygis ; feven
belong to the neck, the firft of which is called at-
las, becaufe it immediately fupports the head ;• its
upper fide has two cavities, into which the apo-
phyfes of the os occipitis are received ; but thefe
two cavities together, unlike all other joints, are
laterally portions of concentric circles, by which
means they are but as one joint, and fo fufFer the
head to move eafily fide-ways, which otherwife it
could no more do than the knee, which alfo has
two heads and two cavities. The under fide of
this bone has a very flat articulation with the next,
which fits it for a rotatory motion. The fecond
vertebra is called dentata, or axis, from a procefs
which pafTes through the former bone, and is the
axis upon which it turns ; neverthelefs all the ver-
tebra of the neck contribute fomething to the rota-
tory motion of the head. The proceflus dentatus
is ftrongly tied to the os occipitis, and to the atlas
by ligaments to prevent its hurting the fpinal
marrow. - Twelve of which belong to the back,
five to the loins.-. The os facrum is fometimes five,
fometime fix bcnes, and the os occygis four.-.t If
this chain had been compofed of fewer bones,
they muft have either not been capable of bending
fo much as they do, or have bent more in each
joint, which would have preffcd the fpinal mar-
row, the ill confequences of which are fufficient-
ly feen in perfons grown crooked, or who have
had diftcrtions from external accidents.

The

of the TRUNK. 23

The uppermoft vertebras of the neck being
fixed behind the centre of gravity of the head, the
neck is therefore fo far bent forward, as that the
laft of thefe vertebrae (which has a firm bearing
upon thefe of the thorax) may be exactly under
the centre of gravity. Thofe of the thorax are
bent backwards, behind the center of motion, to
make room for the parts contained in the thorax ;
and that they might not be made too weak by the
ftructure, they are formed for lefs motion than
other vertebrae ; and thofe in particular, which are
bent fartheft from the centre of gravity have the
leaft motion. The middle vertebrae of the loins
are again bent forwards under the centre of grav-
ity, or near it ; and from thence they go back-
wards to the os facrum, where being fixed to the
oira innominata behind the centre of gravity, the
articulation is therefore firm and without motion,
and from thence the offa innominata are fo form-
ed, as that their fockets, into which the thigh
bones are fixed, where there is a free motion, are
exactly under the centre of gravity. In brutes
the fpine is differently formed, according to the
actions for which they are defigned.

In all thefe vertebrae, except the firft, is a mid-
dle anterior fpongy body, by which they are firmly
articulated with a very ftrong intervening liga-
ment ; and from the middle cf the hind part of
each, except the firft, (lands a procefs named fpi-
nalis, and from every one a procefs on each fide,

called

24 Of the BONES

called tranfverfalis, and two fuperior, and two in-
ferior fhort ones ; by which the back parts of the
vertebras are articulated, named obliqui, fuperiores,
and inferiores.

The fore part of the feven vertebra of the
neck, and two upper of the back, are flat for-
wards, to make room for the afpera arteria an-
gula : The third and fourth of the back acute, to
give way to the veffels of the lungs and heart, and
bent to the right fide for the better fituation of
the heart, which makes that fide of the breaft
more convex than the other, and therefore ftrong-
er ; which feems advantageous to the right arm,
its motions depending upon the fupport it receives
from the breaft. Hence, I think, it feems, that
the aimoft univerfal preference of that arm is not
an arbitrary thing, but founded upon obfervation,
that it is capable of more perfect actions than the
other.

The fpinal procefies of the fecond, third, fourth,
and fifth vertebras of the neck are forked, the two
Lift long and horizontal, the three or four upper
ones of the back like them, only a little declining,
the middle ones of the back run obliquely down-
wards, and the procefies of the remaining vertebra:
become fucceflively thicker, ftronger, and lefs de-
clining ; thofe of the loins being horizontal, like
the laft of the neck. The mufcles, that are inferted
into the fpinal procefies of the vertebras of the
neck and loins will ad with more ftrength than thofe

of

OF THE TRUNK. 25

of the back, becaufe their procefles being perpendic-
ular to the fpine, they are longer leavers : befides,
thofe of the back almoft touch one another, to pre-
vent much motion, becaufe it would interrupt res-
piration ; but more motion being necelfary in the.
neck and loins, their procefles are made fit for it.

The tranfverfe procefles of the vertebrae of the
neck are perforated, for the admiflipn of the cer-
vical blood veffels, and bowed downwards, and
hollowed, for the paflages of the cervical nerves.
The eight or nine upper ones of the back receive
the upper ribs ; and the reft, with thofe of the
loins, ferve only for origins and infertions of muf-
cles.

f Os facrum has two upper oblique procefles,
fome fmall fpinal procefles, and two foramina in
each interftice of the bones it is compofed of, both
before and behind. Ofla coccygis have none of
thefe parts.:

Through every bone of the fpine, the ofla
coccygis excepted, is a large foramen, which to-
gether make a channel through the fpine, in which
is contained the medulla fpinalis ; and in each
fpace between the vertebrae are two large holes for
the nerves to pafs out.

It is worth confidering the provifion which is .
made to prevent luxations in this chain of bones,
fuch luxations being worfe than any other, becaufe
of the fpinal marrow which is contained within thefe
bones. The bodies of the vertebrae are all in the
C fame

i6 Of the BONES

fame manner connected by ftrong intervening liga-
ments or cartilages. In the neck the oblique pro-
ceffes of the received bone are wrapped over thofe
of the receiving bone, which forbids their luxating
forwards. The tranfverfe proceffes, with a fmall
apophysis of the body of the fame bone, in like
manner, fecure them from flipping backwards*;
and an apophyfis on each fide of the body of the
receiving bone, hinders them from flipping to either
fide. The vertebras of the back are hindered from
diflccating forwards by the fame provifion with
thofe of the neck ; and from luxating backwards,
by the ribs which are faflened to the tranfverfe pro-
ceffes of the inferior vertebrae, and againft the back
part of the body of the next fuperior : they alfo
hinder them from dillocating to either fide ; bul
the laft ribs are not fixed to the tranfverfe proceffes
of the vertebrae of the back, and therefore it is that
luxations are moft frequently feen in this part ; but
the vertebrae of the loins are received into deep
cavities, and are tied with much ftronger ligament 1 ;
for their fecurity. Each joint of the vertebrae, ex-
cept the two uppermoft, has two centres of mo- .
tion, one upon the bodies of the vertebrae, when
the trunk is bowed forward ; and the other at the
articulations of the oblique proceffes, when the
body is bowed backwards ; from which ftru&ure
the extenfors will have about twice the leaver to
ad with, and confequently twice the power to raile
the trunk into an erecl: poiture, that they have to

carry

of the TRUNK. 37

«arry it beyond that pofture : for then the oblique
proceffes begin to be the centre of motion, and give
a like advantage to the benders. Without this con-
trivance it would be more difficult to keep the body
erecT:, or to recover an erect pofture with consider-
able ftrength after a bend of the body.
• The ribs are twelve in number on each fide ;
the {even uppermoft are called true ribs, becaufe
their cartilages reach the fternum ; and the five
lowed are called baftard ribs. : They are articulated
to the bodies of the twelve vertebrae of the back,
and all, except the two or three laft, are articu-
lated to their tranfverfe proceffes, and the under
fide of the middle ribs are hollowed for the pafTage
of the intercoftal veffels. They defend the p arts
contained in the breaft, and when they are drawn
upwards, the cavity of the breaft is enlarged for
infpiration, and fo the contrary. In two children,
which I have duTected, I found the ribs broke in-
wards, and on the outfide a very plain print of a
thumb and fingers, occafioned by their nurfes tak-
ing hold of their breafts, and hoifting them up on
one hand, which being often repeated, had broke
the ribs inwards like a green flick, without feparat-
ing the broken ends of them. I have alfo very fre-
quently feen the mape of children's breafts quite
fpoiied by fuch tricks, which have occafioned weak-
nefs of body, crookednefs, and other difeafes.

Sternum, or breaft-bone, is generally made up
sf three fpongy bones, fometimes more ; to this the

C 2 t w o ^**-«— -

:§ Of the B O N E S

-4w«t ribs are articulated by their cartilages, which
fometimes in robuft men have moveable joints,
fuch as are ieen in oxen and other quadrupeds. ;
At the end of the fternum is the cartilago enfifor-
mis, fo called from its ihape, but it very often is
double ; there is alfo frequently found variety in
the form of the cartilages, which join the ribs and
fternum ; fometimes one cartilage ferving two ribs,
and fometimes a cartilage not joined to any rib ;
frequently in old perfons we find parts of them of-
fified, and I have twice found them totally offified
in men between forty and fifty years of age, both
of which died with a great difficulty of breathing ;
and befides, one had a jaundice, and the other a
dropfy, but the lungs in both were very found.
« There are feldom found fewer than four and
twenty vertebras in the fpine, befides the os facrum,
but often more ; fometimes thirteen of the back,
with as many ribs of a fide :• and fometimes fix in
the loins, and in fome bodies two ribs from the firft
vertebra of the loins, but then it has wanted tranf-
verfe proceffes.

• Os Innominatum is in young perfons compof-
ed of three bones ; the upper is named ilium,
the lower and pofterior os ifchii, and the anterior
os pubis : the upper edge of the ilium is called its
fpine, the anterior part of the fpine its apex, and a
little lower is the proceffes innominatus. * Ilium
has two proceffus, the one named the obtufe pro-
cefs, and the other the acute ; in the centre of

thefe

OF THE TRUNK. 29

thefe bones is the acetabulum or focket for the
thigh bone ; in the bottom of which focket is^an-
other cavity, in which lies the lubricating gland of
this joint. When impoftumations happen in this
joint they ufually caufe a great fwelling and lame-
nefs in the hip, which, in time, makes a colle&ion
of matter in the external part of the hip ; how-
ever, this is not the only way it proceeds, for I
have twice feen the matter in the joint make way
through the bottom of the acetabulum into the pel-
vis of the abdomen ; in thefe cafes, when the pa-
tient went to ftool, the matter, by flraining, was
preffed out through the external wound.

CHAP. IV.

Bones of the Upper Limb*

CLAVICULA is -connected at one end to the
fternum with a loofe cartilage, and at the other
to the proceffus acromion of the fcapula ;» its
chief ufe is to keep the fcapula a fufficient diftance
from the breaft, by which' means the moulders are
hindered from coming near together, as they do in
thofe quadrupeds which ufe their fore limbs only
to walk on, and not as men do their hands.

Scapula is fixed to the fternum by the clavi-
i;ula', but its chief connexion is to the ribs and

fpine.

JO B O N E S OF THE

fpine, by thofe mufcles which are made alfo for its
various motions ; • and in fuch quadrupeds as have
no clavicles it is fixed only by mufcles, whofe
actions give to this bone a great deal of that mo-
tion which feems to be in the joint of the fhoulder.
The under fide of this bone is a little concave,
partly to fit to the outer furface of the ribs on
which it moves, and partly to give room for the
fub-fcapularis mufcle. „ • On the outfide arifes a
large fpine ; the fore part of which is called the
proceffus acromion, to which the clavicula is fixed..
In men and fuch quadrupeds as have clavicles, and
life their fore limbs like arms, this procefs and
fpine are much larger and more prominent, not
only for the better fixing the clavicle, but alfo to
remove the mufcles farther from the centre of
motion, whereby they are able to move a greater
weight. Near this procefs is another called cora-
coides, from whofe extremity, with like advan-
tage, arife two mufcles of the arm ; this procefs
with the former and a flat ligament between them
both, hinder the os humeri from being diflocated
upwards. The fide oppofite to the focket is called
the bails of the fcapula, and the lower edge cofta
inferior from its figure, which is thick, and like a
rib to the fcapula ; but its upper edge being very
thin, is improperly fo called in the human fkele-
ton, though not fo in many quadrupeds. At the
fore part of this edge, clofe to the coracoid pro-
cefs, is a femicircular mch for the pafTage of blood

veffels,

UPPER LIMB. 31

•veflels, which nich is joined at top with a ligament,
and fometimes with bone.

0$ humeri; its upper end or head, where it is
joined to the fcapula, is fomewhat flat, and much
larger than the focket which receives it. j At the
upper part are two procefTes for the infertions of
mufcles of the arms ; between thefe procefies is a
long channel, in which lies a tendon of the bifeps
cubiti. At the lower end are two confiderable
procefTes, both formed to give origins to mufcles
of the wrift and fingers ; and the flexors of thefe
joints being much more confiderable than the ex-
tenfors, the inner procefs from which the flexors
arife is therefore much larger than the outer, from
which the extenfors take their origins : between
thefe procefTes is the joint. That part to which
the upper end of the radius is fixed, is fitted not
only for the motion of the elbow, but aifo for the
rotatory motion of the radius ; the reft of this
joint is made of portions of unequal, but concen-
tric circles, like the fhanks of quadrupeds ; which
inequality prevents the ulna from diflocating fide-
ways, which fo fmall a joint with fo much motion
would be very fubjeet to. Of a like ufe is the little
finus on the fore part of the humerus, and the large
one behind ; the firft of which receives a procefs of
the ulna when the arm is bent, and the other, the
olecranon, when the arm is extended.

Ulna : at the upper end it has one large pro-
cefs called olecranon, and a fmall procefs .on the

fore

32 BONES op the

fore part ; and on one fide between thefe is alfo
a fmall cavity, which receives the upper end of
the radius for its rotatory motion ; and down the
fide of this bone, next the radius, is a fharp edge,
from which the ligament arifes, which conne&s
thofe bones together. At the lower end is a pro-
cefs, called ftyliformis, and a round head, which is
received into the radius for the rotatory motion of
the cubit, :

Radius : its upper end is received into the ulna,
and joined to the humerus, in a manner chiefly
fitted for its rotatory motion, for the ftrength of the
elbow joint receives but little advantage from the
union of thefe two bones.-. A little below this
head is a large tubercle, into which the biceps
mufcle is inferted, which by the advantage of this
infertion turns the cubit fupine, as well as bends it.
At the lower end, which is thicker, is a focket to re-
ceive the carpus, and at the fide next the ulna a
fmall one to receive that bone, and a thin edge, into
which the tranfverfe ligament, which arifes from
the ulna, is inferted. This ligament ties thefe bones
conveniently and firmly together : for the ulnabeing
chiefly articulated to the os humeri, and the radius
to the carpus, a weight at the hand, without this
ligament, would be liable to pull thefe bones
alunder.

Of the bones of the hand : Carpus is compofed
of eight bones of very irregular forms, undoubted-
ly the propereft that can be ; yet why in thefe

forms

UPPER LIMB. 33

forms, rather than any other, no one has been
able to fhew. ; They have all obfcure motions one
with another, and with thofe of the metacarpus ;
but the motion of thofe of the firft rank, or or-
der, with thofe of the fecond is more confiderable,
and are moved by the fame mufcles which move
the carpus on the radius. The metacarpus con-
fifts of four bones which fuftain the fingers ; that
of the fore-finger having the leaft motion, and
that of the little one the moft : the other ends of
thefe bones have round heads for the articulations
of the fingers ; but the other joints of the fingers
double heads and fockets. The thumb is fhorter
and ftronger than any of the fingers, becaufe in
its actions it is to refift them all. The firft joint
is very fingular, each bone receiving and being
equally received. The bones of the fingers on
the infide are flat and a little hollow, which is nee-
effary to make room for the flexors of the fingers,
and to render their fhape proper for grafping ;
but this leffening their diameters, and confequent-
ly weakening them in the direction in which they
are moft liable to be broke, fuch inconvenience is
provided againft by a larger fubftance.

C H A P.

34 B O N E S of the

CHAP. V.

Bones of the lower Limb.

O S Femoris at its upper end has a round head
which is received into the focket of the os in-
nominate m. ; In moft quadrupeds this head is ob-
long, and makes a firmer articulation ; but that
ihape will not allow of fo much motion as a round-
er head. • The two procefies near the head are call?
ed the greater and leffer trochanters, ;which are
evidently formed for the infertion of mufcles, as
the neck which lies between thefe and the head, is
formed to make room for that neceffary quantity of
mufcles which are feated on the infide of the
thigh, and alfo by projecting outwards to make
long levers for the mufcles, which are inferted
into its upper and external parts. Between the
great trochanter and the neck is a large finus, into
which mufcles are inferted • between the two tro-
chanters is a remarkable roughnefs for the fame ufe,
from which begins the linea afpera. The middle
of this bone, for the convemency of the mufcles,
is bent forwards, which would make it fubjed to
break backwards, if there was not a ftrong ridge
on the back fide, which ftrengthens it fufficiently,
and ferves alfo for advantageous infertions for fev-
cral mufcles ; this ridge is called the linea afpera,
• At the lower end of this bone are two large heads,

called

LOWER LIMB. 35*

called the outer and inner apophyfes :• thefe are fo
tontrived, partly from being projected backwards,
and partly from their fhapes, as to remove the cen-
tre of motion very far behind the axis of the bone,
which gives great power to the mufcles that ex-
tend this joint to raife the whole weight of the
body, though it leffens the power of the benders
which move the leg only ; between thefe pro-
cefTes the large veflels defcend fecurely to the leg.
• Patella is feated on the fore part of the knee ;
its firft appearance is in the centre of the tendon,
through which it foon extends, until the tendinous
fibres are loft, and appear to be converted into
bone ;#' however, when this bone is broke, the orig-
inal tendinous fibres feem to prevail, feeing the
broken parts, unlike all other bones when frac-
tured, unite with a tendon-like fubftance, which
is rarely converted into bone, and efpecially in
thofe cafes where the joint recovers with mod
motion : its ufe is to fecure the extenfors of the
tibia, left, pafling over the joint, they might be
too much expofed to external injuries ; it alfo in-
creafes the advantage (mentioned in the laft para-
graph) of removing the common axis of the exten-
fors of the tibia farther from the centre of motion,
and is a moft convenient medium for thofe muf-
cles to unite in, to perform one common action.
• Tibia, the fhin bone, is large at its upper end,
where are two mallow fockets which receive the
thigh bone j between thefe is a rough procefs, to

which

36 BONES or the

which the crofs ligaments of this joint are con-
nected.; Near the upper end is a prOcefs, into
which -the ligament or tendon of the patella is in-
ferted, and at the lower end is the procefs, which
makes the inner ancle, and fecures this bone from
dhlocating outwards. Towards the upper end
this bone is triangular, and even concave on the
fide next the mufcles to make room for them ;
but lower, as the mufcles grow lefs and tendinous,
the bone grows rounder ; that being upon the
whole a ftronger form ; yet it is not made fo
ftrong as the thigh bone, though it bears a greater
weight, which it is able to do by being ftraighter,
fhorter, and bearing the weight of the body in a
more perpendicular direction.
• Fibula is feated on the outfide of the tibia ;
its upper end is joined to that bone below the joint
of the knee, and its lower end is received into a
ihallow finus of the fame bone, and below that
makes the external ancle ;» which procefs, with the
procefs of the tibia, ftrengthens the ancle joint,
which neverthelefs, being fo fmall, would have
been not ftrong enough, if it had been made for
more motion. It is doubtful to me, whether or
not this bone contributes to the fupport of the
body ; but its great ufe is for the origins of mufcles,
and even its fhape is fuited to theirs.
♦ Of the bones of the foot : Tarfus is compofed
of feven bones, the firft of which, called aftraga-
lus, fupports the tibia, and is fupported by the os

calcis,

LOWER LIMB. $y

calcis, which heing projected backwards, makes a
long lever for the mufcles to a£t with, that extend
the ancle and raife the body upon the toes. ; Thefe
two bones have a confiderable motion between
themfelves, and the aftragalus alfo with the os na-
vicular, and all the reft an obfcure motion one
with another, and with the bones of the metatarfus,
the greateft part of thefe motions being towards
the great toe, where is the greateft ftrefs of action :
thefe bones thus giving way are lefs liable to be
broke, and, as a fpring under the leg, make the mo-
tions of the body in walking more eafy and grace-
ful, and the bones which are fupported by them
lefs fubjedt to be fractured in violent actions. To
thefe join five others, called the metatarfal bones ;
that which fupports the great toe is much the larg-
eft, there being the greateft ftrefs in walking ;
under the end of this lie the two fefamoid bones,
which are of the fame ufe as the patella ; the great
toe has two bones, the lefTer three each, the two
laft of the leaft toes frequently grow together.

Children are fometimes born with their feet
turned inwards, fo that the bottom of the foot is
upwards : in this cafe the bones of the tarius, like
the vertebras of the back in crooked perfons, are
fafhioned to the deformity. The firft knowledge
I had of a cure of this difeafe was from Mr. Pre s-
grove, a profeffed bone-fetter, then living; in
Weftminfter. I recommended the patient to him,
not knowing how tc cure him mvfelf. His way was

by

38 BONES of the

by holding the foot as near the natural poflure as
he could, and then rolling it up with ftraps of
flicking plafter, which he repeated from time to
time, as he law occafion, until the limb was re-
ftored to a natural pofition, but not without fome
imperfection, the bandage wafting the leg, and
making the top of the foot fwell and grow larger.
After this, having another cafe of this kind under
my care, I thought of a much better bandage, which
I had learnt from Mr. Cowper, a bone-fetter at
Leicefter, who fet and cured a fracture of my
own cubit when I was a boy at fchool. His way
was, after putting the limb in a proper pofture, to
wrap it up in wrags dipped in the whites of eggs,
and a little wheat flower mixed ; this drying, grew
ftiff, and kept the limb in a good pofture. And I
think there is no way better than this in fractures,
for it preferves the pofition of the limb without
ftrid bandage, which is the common caufe of
mifchief in fractures. When I ufed this method
to the crooked foot, I wrapt up the limb almoft
from the knee to the toes, and caufed the limb to
be held in the beft pofture till the bandage grew
ftifF, and repeated the bandage once a fortnight.

The bones are fubject to difeafes from all the
fame caufes that the other parts are, but either from
their hardnefs, infenfibility, or other caufes, they
neither are fo frequently difeafed, nor do their dif-
eafes appear fo various ; and it is generally of more
confequence what texture the difeafed bone, or part

of

LOWER LIMB. 39

of the bone is of, than from what caufe that difeafe
proceeded ; for when difeafes happen upon the
furfaces of the hard bones, they ufually admit a
cure by exfoliation ; but when matter is made in
the fpongy ends of the cylindrical bones, or in the
bodies of other fpongy bones, the matter, what-
ever was the firft caufe, infinuates itfelf through
thofe fpongy cells, fwelling the bone, and making
generally an incurable caries ; but if the matter is
corrofive, it often ulcerates thefe parts ; and ufually
makes {o large a difcharge as to deftroy the patient
where the part difeafed cannot be extirpated, which
is often the cafe when matter is made in the bones
in fcrophulous habits.

The venereal difeafe rarely attacks any Jmt the
hardeft parts of the bones, very foon raifing large
tumours and caries or mortification ; but thefe cari-
ous parts of bones from this or other caufes are but
partially mortified ; for, were they perfectly fo, the
found and unfound parts would feparate, though the
integuments were not taken off; whence it happens,,
that, where there is a good habit of body, carious
bones are often endured many years without much,
inconvenience ; and we find from experience, that
fuch feparations are not to be made till the difeafed
part is laid bare and perfe&iy mortified, by being
expofed to the air, &c and then the found part un-
derneath feparating from the unfound, there firft
granulates a fungous flefli-like appearance, which,
ought never to be treated with corrofive medicines,

40 B O N E S of tii2

it conftantly fhrinking and hardening of itfelf, be-
ing the fame fubftance which fhoots from the ends
of broken bones, where alfo it foon fhrinks and
converts into a callus to reunite them.

There is a caries diftinc~t from thefe, which I
have only feen in two patients who died after a
long rheumatic diforder, in which the outer fur-
face of all the hardeft bones, as the middle of the
cylindrical bones, and the top of the fcull, in one
w T hich I boiled, and in the other as far as I was
allowed to examine, I found the outer part every
where crumbly or fcaly, falling into pieces like
duft or fand, with very little appearance of tumour
any where, and no appearance of difeafe in the
fpongy parts.

Sometimes matter is formed in the large me-
dullary cavities of the cylindrical bones, which con-
ftantly increafing and wanting vent, partly by cor-
roding and rendering the bone carious, and partly
by preimre, tear afunder the ftrongeft bone in an
human body, of which I have known feveral in-
ftances. In one cafe where the matter had fuffic-
ient difcharge by an external caries formed together
with the internal one, all the internal hard part of
the bone which contains the medulla was feparated
from the reft ; and being drawn out through the
place where the external caries made a vent, the pa-
tient received a perfed cure. In another cafe of this
kind, where the internal part which contains the
medulla was alfo feparated from the reft, and there

being

LOWER LIMB. 41

being holes through which the matter was difcharg-
ed, but none fufficient to take out the exfoliated
bone ; the matter continued to flow in great quan-
tity till it deftroyed the patient ; and poflibly, if
this cafe had been rightly known, the internal ex-
foliated part might have been taken out, and the
patient cured. In both thefe cafes, it feems as if
only fo much of the internal part of the bone was
become carious, as receives nourifhment from the
artery which enters the middle of the bone ; and as
a caries is a mortification of a bone, might not this
difeafe arife from a hurt in the veffel which nourifhes
that particular part ?

CHAP. VI.

Cartilages, Ligaments, &c.

EVERY part of a bone which is articulated
to another bone for motion, is covered or lin-
ed with a cartilage, as far as it moves upon, or
is moved upon by another bone in any action ; for
cartilage being fmoother and fofter than bone, it
renders the motions more eafy than they would
have been, and prevents the bones wearing each
other in their actions.

In each articulation of the lower jaw, there is a

loofe cartilage, upon which the condyloid procefs

moves on one fide, while the jaw is moved to the

D other ;

4 2 CARTILAGES,

other ; and the two proceffes being thus raifed at
once ; the jaw is thruft forward. Thefe cartilages
are alio found in animals that chew the cud, but
not in beafts of prey, as far as I have examined,
their articulations being alfo deeper and firmer ; and
in the otter particularly, fections of the fockets,
which receive the condyloid procefles of the lower
jaw, are more than half circles ; fo that the jaw
cannot be diflocated directly without breaking the
fockets. This ftructure renders the motions of the
jaw more firm, as that with intervening cartilages
makes it more loofe and voluble. There are alfo
cartilages of this kind between the clavicles and the
fternum.

In the joint of the knee are two loofe, almoft
annular cartilages, which being thick at their outer
edges, and thin at their inner ones, they make the
greateft parts of the two fockets in this joint. The
ufe of thefe cartilages is to make variable fockets to
fuit the different parts of the lower end of the os
femoris ; for none but a round head and a round
cavity can fuit in motion, unlefs the fhape of one
or the other alters ; and it is plainly neceffary, that
this lower end of the os femoris mould be nattifh,
and projected backward, to give advantage to the
mufcles that extend the tibia, by fetting the centre
of motion backward : which mechanifm, though
it equally lefTens the power ofthofe mufcles which
bend this joint, is yet of great fervice, becaufe the
extending mufcles move this joint under the weight

of

LIGAMENTS,&c. 43

of the whole body, but the flexors only raife the
legs ; and as no head or focket moves fo eafily as
round ones, here feems to be fome provifion made
againft the inconvenience of a flattim head and cav-
ity, by having the fri&ion made upon two mrfaces,
the os femoris upon the loofe cartilages, and the loofe
cartilages upon the tibia. This contrivance is prac-
tifed by mechanics, where the friclion of the joints
of any of their machines is great, as between the
parts of hook-hinges of heavy gates, and between
the male and female fcrews of large vices, where
they ufually place a loofe ring.

There are other cartilages which ferve to £wd
lhape to parts. Of this fort are the ciliary or
ages at the edge of the eye-lids, the cartilages of
the outer ears, and thofe which compofe the lower
part of the nofe, which have this particular advan-
tage in thefe places, that they fupport and fhupe
the parts as well as bones do, and without being
liable to be broke ; and to thefe might be added
thofe of the larynx, but they do not belong properly
to the fkeleton.

Bones that are articulated for motion are ti-
ed together by very ftrcng ligaments, to pre-
vent their diflocating, which a!fo, r |urround the
joints to contain their lubricating mucus. The
thicknefs and ftrength of thefe ligaments are pro-
portioned to the actions of the feveral joints, and
their lengths are no more than fufficient to allow a
proper quantity of motion ; but the forms of them
D 2 are

44 CARTILAGES,

are different according to the different actions of the
feveral joints.

The bones of the limbs that move to all fides
have ligaments like purfes, which arife from or
near the edges of the fockets of the receiving bones,
and are inferted all round the received bones a little
below their heads. The beginnings of thefe liga-
ments, from the edges of the fockets of the fcapula
and os innominatum, are very hard, almoft cartila-
ginous, which ferves in the fcapula to make a larg-
er focket, and fuch an one as will alter the figure
as the bone moves, for the reafon I have mentioned
in the loofe cartilage of the knee : for the head of
the os humeri not being an exacl: portion of a fphere,
requires fuch a focket, and the hard part of this liga-
ment of the focket of the os innominatum makes
the focket deeper than the femidiameter of the
focket, by which means the articulation is made
ftronger without any hindrance to motion, becaufe
it will give way to the neck of the os femoris when
it preffes againft it ; and the thigh bone being more
difpofed to be diflocated upwards than any other
way, the upper fide of this burfal ligament is made
exceeding flrong to prevent fuch an accident. From
the lower edge of the acetabulum or focket of the
os innominatum arifes a ligament about an inch
long, called teres, or rotundum, which length is
neceffary for that quantity of motion which this
joint has in human bodies ; it alfo hinders the os
femoris from diflocating upwards, but downwards

it

LIGAMENTS, &c, 45

lt will fuffer it to go far out of the fockct ; but in
brutes the head of the os femoris being oblong,
and the cavity fuitable, there can be only* a rota-
tory motion, which in effect will be very little
more than that kind of motion which is called
bending and extending ; and this never removing
the end of the head of the bone far in the focket,
a fhort ligament is enough for it, and will better
keep the bone in its place ; and therefore it is that
theirs is fo fhort. This ligament in men may alfo
ferve to prefs the gland in the bottom of the aceta-
bulum or focket.

The ligaments of thofe joints which admit only
of flexion and extenfion, differ from the former
in this, that they are much fhorter and ftronger at
the fides of the joints, and thinner backward and
forward. Befides thefe ligaments, in the middle
and back part of the joint of the knee, are two very
ftrong ligaments, which arife from a procefs at the
end of the tibia. They crofs each other in fach a
manner, as is beft to fecure the joint from being
difplaced any way ; they alfo hinder the extenfors
of the tibia from pulling that bone too far for-
wards, and are fo connected to the femilunar cartil-
ages, as to move them as the joint moves ; be-
fides thefe, in this joint is another fmall one, which
arifes from the os femoris, and ends in the fatty
membrane which it fupports. The knee, I think,
cannot be completely diflocated without breaking
the crofs ligaments : I have feen thjs cafe but once,

the

4^ CARTILAGES,

the bone indeed was eafily reftored to its place,
but to no purpose.

The bones of the carpus and tarfus are tied to-
gether by ligaments running promifcuoufly upon
their furfaces from one to another ; which at the
under fide of the tarfus are vaftly ftrong, becaufe
they fupport the" whole body ; thefe ligaments to-
gether contain the mucus for all thofe joints. There
is alio to the carpus a ftrong ligament, which runs
from the fifth bone to the eighth, and the procefs
of the fourth bone : the proper ufe of this is, to
bind down the tendons of the mufcles that bend the
fingers. x •

The proceffus dentatus of the fecond vertebra is
tied to the fcull by a ligament, and kept clofe to
the forepart of the firft vertebra by another\in that
vertebra, that it may not bruife the fpinal mar-
row ; and when either this ligament or procefs is
broke, it makes that fort of broken neck which is
attended with fudden death. All the bones of the
vertebra?, and every joint that is without motion,
and not joined by a future, as the ofTa innominata
with each other, and the os facrum with the ofla
innominata, are joined by intervening ligaments,
or, as they are commonly called, cartilages. The
offa innominata are alfo tied by very ftrong liga-
ments which run from the back parts of the fpines
of the ofla ilia to the os facrum, and other liga-
ments which go from the os facrum, and os coccy-
gis to the acute and obtufe procefles of the ofla i&

cfria;

LIG AMENTS, &c. 4/

chia : thefe ligaments ferve alfo for origins of muf-
cles. Towards the great foramen of the ofTa inno-
minata the acetabulum has a deep notch, from the
one fide to the other of which runs a ligament
which completes the focket ; this ligament is fome-
times offified : a ligament fomewhat like this there
is between the proceffes of the fcapula.

From the edge of the ilium to that of the os
pubis, runs a ligament which is contiguous to,
and appears to be a part of, the tendons of the muf-
cles of the abdomen ; its ufe is to cover the iliac
veflels as they defcend to the thigh. Under this
ligament, together with the vefTels, I have often
feen a rupture of matter, and, I think, fometimes
of the gut, from the abdomen into the anterior
part of the thigh, immediately below the groin :
however, I dare affirm this to be a poffible cafe.

It is generally agreed, that the ligaments are in-
fenfible, and the reafon affigned is, that they would
elfe be injured by ordinary motions. But they are
much better contrived ; feeing none of them, not
even thofe which lie between the vertebra?, are fub-
ject to attrition ; but the other, experience fhews,
are capable of very acute pains ; there being not
any thing our patients more grievoufly complain of,
than collections of matter within thefe parts, or
fharp medicines applied to them, when laid bare.

Every joint, where the bones are faced with a
cartilage for a Aiding motion, is furnifhed with
fmall glands, which feparate a mucilaginous mat-
ter

48 CARTILAGES,

ter for the lubricating of the ends of the bones, that
they may move eafily upon one another ; and that
there may be no wafte of this neceffary fluid, it is
contained in the inverting ligaments; which, for this
very reafon, are no where divided, except to com-
municate with the ligaments of the tendons.

Thefe glands are generally feated in a little fat
near the infertion of the ligaments, that they may
be compreffed by them when the joints are in mo-
tion ; which is a proper time to have their fluid
preffed out. The moft confiderable parcel of thefe
glands, with their fat, are feen in the joint of the
knee, and the largeft gland of this fort is found in
the fmus at the bottom of the acetabulum of the
os innominatum, and is compreffed by the liga-
mentum teres.

The difeafes of the joints either happen from
ulcers in the lubricating glands, which, pouring out
matter that cannot be difcharged, foul the ends
of the bones, or elfe from fwellings in the ends of
the refpedive bones. Either of thefe in time create
exceffive pain, which appears to me to be chiefly
in the ligaments of the joints, notwithftanding what
has been faid of the infenfibility of thefe parts.
When a joint is much fwelled and painful, with-
out external inflammation, it is vulgarly called a
white fwelling, and more properly fo than fpina
vcntofa. It is fometimes in the beginning cured
by evacuations, but when the limb waftes below
the fwelling, and the fingers or toes of the limb

grow

LIGAMENTS, &c. 49

grow thinner at their joints, and lofe their fhape,
the cafe then is abfolutely irrecoverable. Some-
times the ends of the bones erode, then join to-
gether and form an anchylofis, which, though a fe-
vere difeafe of itfelf, yet it is often a remedy of one
that is much worfe. In like manner the bones of
the hands and feet, when they are ulcerated, fome-
times unite, and are thus preferved from total ruin.
But there is one cafe of a white fwelling that is
amazing, where the pain is fo great that we are
forced to take off the limb, and yet neither find
upon dhTecTiion the ligaments or glands difeafed,
nor matter in the joint, nor the bones carious, or
any difeafed appearance, except that the ends of
the bones are a little larger and fofter.

TAB.

( So )
TAB. I.

A, The fkeleton of a child twenty months old,
in which all the bones differ in fhape from
thofe of an adult. The fcull is much larger
in proportion, and the bones of the limbs with-
out thofe roughnefTes and unevenneffes which
afterwards appear ; their texture is every where
more loofe and fpongy, and their outlines what
the painters call tame and infipid ; their ex-
tremities are feparate and formed cartilaginous,
which is accurately diftingiiiihed in the plates
by the manner of graving.

B, The thigh bone of a man, fawed through, in
the middle of which is feen the cavity which
contains the oily marrow, and at the extremities
the leffer cells, which contain the bloody mar-
row. The white line acrofs the head of this
bone, beginning at the fingers of the fkeleton, is
the place where the epiphyfis and the bone are
united. A' like line, acrofs the lower end of
this bone, fhews there the fame thine.

C, The os bregmatis of a fcetus fix months old,
which fhews the fibres oflifying from the cen-
ter to the circumference.

TAB.

tab r

J°.Jo.

TAR Jl.

( 5* )
TAB. II.

i Os frontis.

2 Os bregmatis,

3 Os temporis.

4 Os occipitis.

5 Os malse.

6 Os maxillae fuperioris.

7 Os nafi.

8 Os planum.

9 Proceflus maftoideus.

10 Proceflus ftyloides.

1 1 Proceflus pterygoides.
\% Dentes.

13 Proceflus coronalis.

14 Proceflus condyloides,

15 Dentes.

TAB.

( 5* )

»

TAB. Ill,

1 Os frontis. «*

2 Os bregmatis.

3 Os occipitis.

4 Sella turcica.

5 A procefs of the os fphenoidcs, making part of

the feptum nafi.

6 A procefs of the os ethmoides, making part of

the feptum nafu

7 Vomer.

8 Crifta galli, before which is feen in fhadow the

finus frontalis.

9 The cornua of the os fphenoides.
io Sella turcica.

1 1 Os frontis.

1 2 Crifta galli and os ethmoides.

1 3 Sinus frontales.

14 Sella turcica.

15 The fifth foramen.

16 Proceffus jugales.

17 Os petrofum.

18 Foramen magnum.

19 The outfide of the os occipitis.

TAB,

TABUL

F.Se,.

Tab.iv.

( 53 )

TAB. IV.

I The fecond vertebra of the neck.
i The tranfverfe proceffes of the vertebra* of the
neck.

3 Clavicula.

4 The proceffus acromion of the fcapula.

5 Os humeri.

6 The ribs.

7 The tranfverfe proceffes of the vertebras of the

loins.

8 The os facrum and os coccygis.

9 Os ileum,
io Os ifchium.

1 1 Os pubis.

1 2 Os femoris.

TAB.

■='•>■

T Alt- VI.

P.JS.

( 55 )
TAB. VI.

1 The head of the os humeri.

2 The outer extuberance.

3 The inner extuberance.

4 That part which joins with the ulna.

5 The olecranon of the ulna.

6 The lower end of the ulna which joins to the

radius.

7 Procelhis ftyloides.

8 The upper end of the radius.

9 The tubercle.

io The part of the radius which joins with the

carpus. .
XI, 12, 13, 14, 15, 16, 17, 1 8, The eight bones

of the carpus.

TAB.

( 56 )
TAB. VII.

1 Radius.

2 Ulna.

3 Carpus.

4 The three bones of the thumb.

5 The four bones of the metacarpus.

6 The three bones of the fingers.

TAB.

TAB VII

t'..

i

a

**1

JO

( 57 )

TAB. VIII.

i The head of the os femoris.

2 The great trochanter.

3 The lefTer trochanter.

4 The lower end which articulates with the tibia.

5 The upper end of the tibia.

6 The lower end of the tibia.

7 The procefs which makes the inner ancle.

8 The upper end of the fibula.

9 The lower end which makes the outer ancle,
io The outfide of the patella.

1 1 The infide of the patella.

/

/

TAB.

( 58 )

TAB. IX.

I Aftragalus.

i Os calcis.

3 Os naviculare.

4, 5, 6, OfTa cuneiformia.

7 Os cuboides.

8 The five bones of the metatarfus.

9 The two bones of the great toe.
io The three bones of the leffer toes.

TAB.

TAB.JX1.

2*38

TAB.X.

(59)

TAB. X,

A fkeleton of an adult put into this pofture
to fhew it in a greater fcale. It was thought bet-
ter not to figure it, all thefe bones being explained
in former plates, and the defign of this being to
fhew them together, without being defaced with
references.

E 2 THE

THE

ANATOMY

OF THE

HUMAN BODY.

BOOK II.

CHAP. I.

Introduction to the Muscles.

. JL HE mufcles are moving powers, applied to
perform the feveral motions of the body ; which
they do by contracting their length, and thereby
bringing the parts to which they are fixed nearer
together. • -The immoveable or leaft moved part
any mufcle is fixed to, is ufually called its origin,
and the other its infertion ; but mufcles that have
their two ends equally liable to be moved, may
have either called the origins or infertions. »

Each mufcle is made up of a number of fmall
fibres, which Borelli and others, have thought

to

62 INTRODUCTION

to be firings of bladders, and have endeavoured to
account for mufcular motion by an expanfion made
from an influx of blood and animal fpirits into thefe
bladders ; but as the mufcles do not increafe their
bulk fenfibly in contracting, there needs no more
to be faid to refute this hypothecs. But another
great author thought that in this way the mufcles
might be contracted by a fwelling, fcarce fenfible,
if the bladders were but very fmall : for, fays he,
fuppofing a bladder of any determined bignefs can
raife a weight a foot, a hundred bladders, whofe
diameters are each a hundredth part of the former,
will raife the weight to the fame height. But the
force of inflation and the fwelling of all together
will be ten thoufand times lefs, and it will alfo
raife ten thoufand times lefs weight, which he
has not obferved ; therefore not one fuch firing of
bladders, but ten thoufand, mufl be applied to do
the fame thing that the one bladder will do ; and
they will have the fame fwelling ; otherwife it
would be eafy to fhew how to make a perpetuum
mobile of almofl any force.

* The mufcles are of two forts, viz. rectilineal,
and penniform. . The former have their fibres al-
mcft parallel, in the fame or near the fame direction
with the axis of the mufcle ; and the latter have
their fibres joined, in an oblique direction, to a ten-
don pafling in or near the axis, or on their outfule..
The rectilineal mufcles, if their origins and in-
fertions are in little compafs, are never of any con-

fiderable

to the MUSCLES. 63

fiderable thicknefs, unlefs they are very long, be-
caufe the outward fibres would comprefs the in-
ner ones, and make them almoft ufelefs ; and
therefore every rectilineal mufcle, whofe inner
fibres are comprefled by the outer, have their in-
ner fibres longer than the external, that they may
be capable of equal quantity of contraction.

The penniform mufcles, though they are in a
manner free from the inconvenience of one fibre
comprefling another, and though by the obliquity
of their fibres, nothing is abated of their moment,
(for in all cafes, juft fo much more weight as recti-
lineal fibres will raife than oblique ones, the ob-
lique will move their weight with fo much greater
velocity than the rectilineal ; which is making their
moments equal : fo that in the ftructure of an ani-
mal, like all mechanic engines, whatever is gained
in ftrength is ibft in velocity, and whatever is gain-
ed in velocity is loft in ftrength) yet the fibres of
the penniform mufcles becoming more and more
oblique as they contract, their ftrength decreafes,
and their velocity increafes, which makes them lefs
uniform in their actions than the rectilineal muf-
cles ; wherefore it feems that nature never ufes a
penniform mufcle where a rectilineal mufcle can
be ufed ; and the cafes in which a re&ilineal muf-
cle cannot be ufed, are where the fhape of a muf-
cle is luch as that the inward fibres would be too
much comprefled, or where rectilineal fibres could

not

64 INTRODUCTION

not have a lever to act with, fuitable to their quan-
tity of contraction, which is the cafe of all the
long mufcles of the fingers and toes. For every
mufcle mull be inferted or pafs over the centre
of motion of the joint it moves, at a diftance
fuitable to its quantity of contraction, and the
quantity of motion in the joint moved ; for if it
was inferted too near, then the motion of the joint
would be performed before the mufcle is contracts
ed all that it can ; if too far off, the mufcle will
have done contracting before the whole motion of
the joint is made. And though the quickncfs and
quantity of motion in a mufcle* will be, caeteris pa-
ribus, as the length of its fibres ; (for if a fibre four
inches long will contract one inch in a given time,
a fibre eight inches long will contract two inches
in the fame time ; and the ftrength of a mufcle
or power to raife a weight, caeterte paribus, will
be as the number of its fibres ; for if one fibre
will raife a grain weight, twenty fibres will raife
twenty grains :) neverthelefs, two mufcles of
equal magnitude, one long, and the other fhort,
will both move the fame weight with the fame ve-
locity when applied to a bone ; becaufe the levers
they act with muft be as their lengths, and there-
fore the penniform and fhort thick, mufcles are
never applied to a hone for the fake of ftrength, nor
long fibred mufcles for quicknefs ; for whatever is
gained by the form of the mufcle, whether ftrength
or quicknefs, muft be loft by their rnfertions into

the

to the MUSCLES. 65

the bone, or elfe the mufcles muft not act all they
can, or the bones have lefs motion than they are
made for.

In the limbs feveral mufcles pafs over two
joints, both of which are liable to move at once,
with force proportionable to the levers they act
with upon each joint ; but either joint being fixed
by an antagonift mufcle, the whole force of fuch
mufcles will be exerted upon the other joint ;
which in that cafe may be moved with a velocity
equal to what is in both joints, when thefe mufcles
act upon both at once. This mechanifm is of
great ufe in the limbs, as I mall fhew in the prop-
er places.

That only we call the proper ufe and action
of any mufcle which it has without the necelfary
affiftance of any other mufcle, and what that is
in a mufcle moving a joint we may always know
in any fituation, and with what force it acts, ce-
teris paribus, by dropping a line, from the centre
of motion of the joint it moves, perpendicular into
the axis of the mufcle ; but in a joint which ad-
mits only of flexion and extenfion, this line muft
alfo be perpendicular to the axis of motion in that
joint, and the action of the mufcles will be in the
direction of that perpendicular line, and the force
with which it acts in any fituation will be, casteris
paribus,«as the length of that perpendicular line.

Each mufcle, fo far as it is diftinct, and is moved
againft any part, is covered with a fmooth mem-
brane

66 I N T R O D U C T I O N, &c.

brane to make the friction eafy ; but where they
are externally tendinous, thofe tendons are often
fmooth enough to make fuch a covering needlefs.
Befides this membrane there is another, known, by
the name of fafcia tendinofa, which deferves to be
particularly confidered. The ftrong one on the
outfide of the thigh, which belongs to the fafcialis
and gluteus mufcles, is of great ufe in raifing the
gluteous farther from the centre of motion of the
joint it moves, to increafe its force : in like -manner
the fafcia detached from the tendon of the biceps
cubiti alters its directions for the fame purpofe, but
thofe on the outfide of the tibia and cubit, &c.=are
only flat tendons from which the fibres-of the
mufcles. arife as from the bones. There are alfo
in many places fuch tendons between the mufcles,
from which each mufcle arifes in like manner ; for
the bones themfelves are not fufficient to give
origin to half the fibres of the mufcles that belong
to them ; befides, if all the fibres had rife from
the bones, they mult have been liable to comprefs
one another very inconveniently.

C H A P.

Of the MUSCLE S. 67

CHAR II.
Of the Muscles.

OBLIQUUS defcendens arifes flefhly from near
the extremities of the eight inferior ribs, the
upper part of its origin being indented with
the feratus major anticus, and the lower lying
under a fmall portion of the latifiimus dorfi.
It is inferted flefhly into the upper part of the fpine
of the ilium, and by a broad flat tendon (which
firmly adheres to a like tendon of the following
mufcle as they pafs over the rectus) into the cs
pubis, and linea alba, which is a ftrong tendinous
line extended from the os pubis to the dernum,
between the mufculi recti.

Obliquus afcendens arifes flefhly under the
former mufcle from the fpine of the ilium, and is
inferted flefhly in the cartilages of the three lowed
ribs, and by a flat tendon into the dernum, and
linea alba, together with the tendon of the forego-
ing mufcle. The line in which thefe two tendons
join on the outfide of the rectus mufcle, is called
femilunaris : and though fo much of this mufcle
as is inferted flefhly runs obliquely upward, yet the
middle and lower part is directed tranfverfe and
downward ; and befide the tendon, which it unites
with the obliquus defcendens, it often detaches
another near the dernum to be inferted with the

tranfverfalis under the rectus.

Pyramidalis

68 Of the MUSCLES.

Pyramidalis arifes from the os pubis, and is
inferted into the linea alba, about three or four
inches below the navel : this and its fellow are
often wanting.

Rectus arifes tendinous from the os pubis, but
flefhy when the pyramidales are wanting, and is
inferted into the lower part of the iternum, near
the cartilago enfiformis. This mufcle is divided
into four or five portions by tranfverfe tendinous
interfections, that it might conveniently bend when
the body is bowed forwards, though this mufcle
mould be then in action ; and thefe interferons
are chiefly above the navel, where it is moft liable
to be bent : befides, being thus divided, its chief
prefTure will not be in its middle, but under the
feveral bellies of the mufcle, and the greatefl below
the navel, where is the longed flefhy belly of this
mufcle, and where the parts in the abdomen feem
to want moft to be fuppbrted.

Tranfverfalis arifes by a flat tendon from the
tranfverfe proceffes of the lumbal vertebrae, and
flefhy from the infide of the ribs below the dia-
phragm, and from the fpine of the ilium j then,
becoming a flat tendon, it paffes under the rectus
to its infertion into the linea alba. Between this
tendon and the peritoneum fometimes water is
found in great quantities, which diflemper is
called the dropfy in the duplicature of the peri-
toneum ; which fhews this membrane has been
aken for part of the peritoneum.

Thefe

Of the MUSCLES. 69

Thefe five pair of mufcles all confpire to
comprefs the parts contained in the abdomen.
The obliquus defcendens on the right fide, and
afcendens on the left acting together, turn the
upper part of the trunk of the body towards the
left, and vice verfa ; but the trunk, is chiefly
turned upon the thighs ; the recti bend the body
forward, and pull the fternum downward in ex-
piration ; the two oblique mufcles and the tranf-
verfe on each fide near the groin, are perforated
to let through the proceffus vaginalis with the
fpermatic veffels. Thefe perforations are diftant
from each other, fo as to fuffer the veffels to
defcend conveniently into the fcrotum : this way
the inteftines or the omentum defcend in rup-
tures.

Cremafter teftis is a fmall portion of fibres
which arifes from the ilium, and appears to
be part of the obliquus afcendens mufcle, till it
meets with the fpermatic veffels at their coming
out of the abdomen, where it begins to defcend
with them by the fide of the proceffus vaginalis,
to the tefticle, over which it is loofely expanded.
This mufcle is too fmall to be plainly difcovered
in emaciated bodies.

Erector penis arifes from the os ifchium, and
is inferted into the crus penis near the os pubis.
It is faid, by prefling the penis againft the os pubis
to comprefs the vena ipfms penis, and hinder the
reflux of blood, whereby the penis becomes ex-
tended

70 Of the MUSCLES.

tended and erect ; but it does not appear to me to
be well contrived for that ufe.

Accelerator urinx. This, with its fellow,
are but one mufcle. It arifes tendinous from the
cfla ifchia, and flefhy from the fphincter ani ; or,
according to Mr. Cow per, from the fuperior part
of the urethra as it pafTes under the os pubis : and
thence, being expanded over the bulb of the
urethra, it afterwards divides, and is inferted into
the penis. The ufe of this mufcle is not to accel-
erate the urine, for that is propelled by the detrufor
urinae, or mufcular coat of the bladder, but to pro-
trude the femen, which is done only by this : and
it being feated oppofite to the os pubis, it feems to
be much better fitted to be a relaxer of the penis,
by pulling it from the os pubis, than the erector
is for the office affigned it.

Tranfverfalis penis is that part of the former
mufcle which arifes from the offa ifchia.

Sphincter veficse urinariae is a fmall portion of
mufcular fibres, not eafily to be diftinguifhed, run-
ning round the neck of the bladder to prevent the
involuntary effufion of urine.

Detrufor urinae is the mufcular coat of the blad-
der ; its fibres are differently difpofed ; but chiefly
terminating in the fphincter vefica, whereby it not
only preffes the urine forward, but, when the blad-
der is full, becomes an antagonift to the fpincter,
acting almoft at right angles.

Erector

Of the MUSCLES. y t

Erector clitoridis arifes from the ifchium, and
is inferted into the cms clitoridis, like the erector
penis in men, and is faid to caufe erection in the
fame manner.

Sphincter vaginge is an order of mufcular fi-
bres, intermixed with membranous fibres, furround-
ing the vagina uteri near its orifice ; it is connect-
ed to the offa pubis and fphincter ani ; its ufe is
to conftringe the orifice of the vagina, to prefs out
a liquor from the glands of the vagina, and em-
brace the penis in coition. ¥

Dr. Douglas mentions two pair of mufcles of
the vagina, of his own difcovering, which I have
never dilfected, and will therefore give them in his
own words ; " The firft arifes from the inner edge
" of the os pubis mid-way between the ifchion and
" the beginning of the crus clitoridis, is inferted in-
" to the vagina ; the fecond arifes tendinous and
" flefhy from the os pubis internally in common
" with the levator ani, is inferted into the upper
" part of the vagina at the fide of the meatus urina-
" rius or collum vefica."

Sphincter ani is a mufcle near two inches in
breadth, furrounding the anus to clofe it, and to
prevent involuntary falling out of the fasces.

Levator ani, by Dr. Douglas called two
pair of mufcles, but Mr. Cowper defcribes the
whole as one mufcle only, which arifes from the
ofla ifchii, pubis, and facrum within the pelvis, and
is inferted round the lower end of the rectum in-
teftinum.

Fiftulse

72 Of the muscles.

Fiftulse in ano, that are within this mufcle,
generally run in the dirc&ion of the gut, and may
be laid open into the gut with great fafety ; but
thofe fiftulae, or rather abfcefTes, that are frequently
formed on the outfide of the fphin&er, and ufually
iurround it, all but where this mufcle is connected
to the penis, cannot be opened far into the gut,
without totally dividing the fphincter, which, au-
thors fay, renders the fphin&er ever after incapable
of retaining the excrement. One inftance of this
kind I have known jfrbut Mr. Berbeck of York, an
excellent furgeon, and particularly famous for this
operation, has allured me, that he has often been
forced to divide the fphincler, which has made the
patients unable to hold their excrements during their
cure, but the wounds being healed, they have re-
tained them as well as ever.

Coccygei arife from the acute procefTes of the
offa ifchii, and arc inferted into the os coccygis,
which they pull forward.

Occipito-frontalis, is a mufcle with four flefhy
bellies, commonly named frontales and occipi-
tales. It arifes behind each ear from the os oc-
cipitis, and foon becoming tendinous, paffes un-
der the hairy fcalp to the forehead, where it be-
comes broad and flefhy, adhering to the fkin, and is
inferted into the upper part of the orbicular mufcles
of the eyelids, into the os frontis near the nofe, and
by two procefTes into the bones of the nofe. When
this mufcle acts from the back part, it pulls the

{kin

Of the MUSCLES. 73

1km of the forehead upward, and wrinkles it tranf-
verfe, and in fome perfons the hairy fc?Jp back-
wards ; but when the fore part of it acts, it draws
the fkin with the eyebrows downward, and towards
the nofe when we frown. The tendon of this muf-
cle has been miftaken for a membrane, and been
called pericranium, and the true pericranium, pe-
riofteum.

Elevator auriculae arifes from the tendon of
the occipito-frontalis, and is inferted into the
upper part of the ear that is connected to the
head.

Retractor auriculas arifes by one, two, or
three fmall portions from the temporal bone above
the mammillary procefs, and is inferted into the ear
to pull it backward.

Orbicularis palpebrarum furrounds the eye-
lids on the edge of the orbit, and is fixed to the
futura tranfverfalis at the great corner of the eye ;
it fhuts the eyelids, efpecially in winking. That
part of this mufcle that lies under the eyebrow is
very much intermixed with the occipito-frontalis ;
and under it, from the os frontis near the nofe,
arifes a fmall portion of diftincl: fibres which end in
this mufcle, and, I think, are a part of it : neverthe-
lefs, from the efFect of their action, are not improp-
erly called mufculus corrugatcr.

Ciliaris is a very fmall portion of this mufcle,
next the ciliary cartilages of the eyelids.

£ Elevator

74 Of the M USCLES.

Elevator palpebral fuperioris rectus rifes above
the optic nerve, from the periofteum at the bot-
tom of the orbit, as do alio the five following
mufcles, and is inferted into the whole ciliary
cartilage of the upper eyelid by a very thin
flat tendon.

Elevator oculi arifes from the bottom of the
orbit, between the optic nerve and the foregoing
mulcle, and is inferted in the upper part of the tu-
nica fclerotis of the eye, near the cornea.

Depreffor oculi arifes, and is inferted directly
oppofite the laft defcribed mufcle.

Adductor oculi arifes from the bottom of the '
orbit, near the optic nerve internally, and is in-
ferted into the tunica fclerotis on the fide next
the nofe.

Abductor oculi has both its origin and infer-
tion directly oppofite to the adductor.

Obliquus fuperior feu trochlearis arifes between
the elevator and adductor oculi at the bottom
of the orbit, thence afcending by the futura tranf-
verfalis, becomes a round tendon, which paffing
through a pulley at the upper and inner part of the
orbit near its edge, is inferted near the bottom of
the globe of the eye, which it pulls upward and
inward, and thereby directs the pupil outward and
downward.

Obliquus inferior arifes from the os maxil-
lae fuperioris, at the edge of the orbit ; thence
paffing over the depreifor is inferted near the ab-
ductor

Of the MUSCLES. 75

ductor at the bottom of the eye, but not fo low
as the infertipn of the obliquus fuperior : it turns
the pupil upward and outward.

Thefe mufcles are inferted with great advan-
tage to move a fmall weight, and are very long,
that the eye may be moved with fufEcient quick-
nefs. The two oblique mufcles are an axis to the
motions of the other four, and acting ftrongly
againft them, which action I take to he what is
vulgarly called itraining the eye, may, I think,
bring the cryftalline humour nearer to the retina,
and poilibly may make the cryftalline humour
more flat to fit the eye for objects at a great dis-
tance. For this end it feems to me that there are
fix mufcles thus difpofed, when three might be
fufEcient to turn the eye every way, if it was in a
proper fixed focket : and it feems alfo, that while
the mufcles are all thus in action, the fuperior ob-
lique in each eye fets the pupil farther from the
nofe, while the inferior oblique directs it upward ;
the firft of which actions is always neceffary, and
the latter often fo, when we look with both eyes
at very diftant objects ; and when the two oblique
mufcles grow weak by age or difeafe, or ceafe to
act at all, as in paralytic cafes, and death, then the
eye finks in the orbit. •

Sphincter, or conftrictor oris, furrounds the
mouth about three fourths of an inch broad. This
mufcle is very much intermixed with all the muf-
fles that are inferted into it.

F 2 Elevator

76 Of the MUSCLES.

Elevator labii fuperioris proprius arifes from
the bone of the upper jaw under the anterior and
inferior part of the orbicularis palpebrarum, and
ufually takes another fmall beginning from the os
milae, which feems as if it was fent off from the
orbicularis palpebrarum ; and pairing down by the
iide of the nofe, into which it fends fome fibres, is
inferted into the upper part of the fphin&er oris.
This raifes the upper lip, and helps to dilate the
nourils.

Deprefibr labii fuperioris proprius is a fmall
mufcle arifing from the upper jaw, near the dentes
inciforii, and is inferted into the upper part of the
lip and root of the cartilages of the nofe ; hence it
is alfo a depreflbr of the nofe, which a&ion con-
itri&s the noftrils.

Depreflbr labii inferioris proprius arifes broad
from the lower jaw at the chin, and is foon infert-
ed into the fphin£ter oris ; the order of fibres in
this feems not (o confpicuous as in the other muf-
cles of the face.

Elevator labii inferioris proprius arifes from the
lower jaw, near the dentes inciforii, and is infert-
ed into the lower part of the lip.

Elevator labiorum communis arifes from a de-
prefled part of the fuperior maxilla under the mid-
dle cf the orbit, and is inferted into the fphinder
mufcle near the corner of the mouth.

Depreflbr communis labiorum ariies later-
ally from the lower jaw near the chin, and is
' inferted

Of the MUSCLE S. 77

inferted into the fphin£ter oppofite to the for-
mer.

Zygomaticus arifes from the anterior part of
the os zygoma or malce, and frequently derives a
portion of fibres from the orbicularis palpebrarum,
thence running obliquely downwards. It is mferted
into the fphincler at the corner of the mouth, be-
twixt the elevator communis and buccinator ; it
draws the corner of the mouth outward and upward.
When this mufcle grows weak, the corner of the
mouth finks, as may be obferved in old perfons.

Buccinator arifes from the procefTus coronse
of the lower jaw, and paffing contiguous to both
jaws, is inferted into the fphincter mufcle at the
corner of the mouth. It ferves either to force
breath out of the mouth, or thruft the aliment
between the teeth in maftication, or to pull the
corner of the mouth outward.

Platyfma myoides arifes loofely from over the
pecloral and part of the deltoid mufcle, and run-
ning obliquely forward, is inferted into the chin,
and depreffor mufcles of the lips. This mufcle
being exceeding thin, a mere membrana carno-
fa, ferves to cover the unequal iurface of the
fubjacent mufcles, and render the neck even ; it
alfo pulls down the corner of the mouth, and, from
its infertion at the chin, may contribute to the pull-
ing down of the lower jaw.

Retra&or alas nafi is a very fmall mufcle arif-
ing from the bone of the nofe, and is inferted

into

7« Of thi: MUSCLES.

into the fkin and cartilage at the fide of the
nofe.

Mylohyoideus with its fellow may be efteem-
ed one penniform or elfe a digaftric mufcle. It
arifes from the linea afpera on the infide of the
lower jaw and proceffus innominatus, both fides
meeting at about right angles in a middle line upon
the following mufcles. It is infcrted by a fmall
portion of fibres into the bafis of the os hyoides ;
it moves the tongue upward and forward, and alfo
compreffes the following mufcles, whereby they
raife the tongue more commodioufly, and alfo hin-
ders them from drawing the bafis of the os hyoi-
des into a right line betwixt the chin and fternum
at fuch times as the ftylohyoidei cannot act

Geniohyoideus arifes from the proceffus in-
nominatus of the lower jaw, under the foregoing
mufcle, and is inferted into the bafis of the os hy-
oides which it pulls upward and forward. This,
with its fellow, are for the raoft part but one
mufcle.

StylohyOideus arifes from the proceffus ftyli-
formis, near its root, and pairing contiguous to the
horn of the os hyoides becomes inferted laterally
into its bafis. This mufcle is fometimes perforated
about the middle, by the tendon of the digaftric
mufcle of the lower jaw. Its ufe is to pull the os
hyoides up and backward.

Coracohyoideus arifes from the upper cofta
of the fcapula, near the proceffus coracoides, and

palling

Of the MUSCLE S. 79

pairing under the maftoideus mufcle becomes in
that place a round tendon ; thence parting almoft
parallel to the following mufcle, is inferted togeth-
er with it into the bafis of the os hyoides ; this
draws the os hyoides downward, and a little back-
ward. I have once feen one of thefe mufcles want-
ing, and the fternohyoideus arifing from the mid-
dle of the clavicle on that fide.

Sternohvoideus arifes from a roushnefs at the
under part of the clavicula near the fternum,
and the cartilaginous part of the firft rib ; and is
inferted into the bafis of the os hyoides, to pull it
downward.

Geniogloffus arifes from the procefTus innom-
inatus of the low T er jaw r , and is inferted broad
into the under part of the tongue, to pull it up and
forward, and fometimes has a fmall infertion into
the os hyoides.

Baiiogloffus feems a portion of the former muf-
cle ; it arifes from the bafis of the os hyoides, and
is inferted into the tongue nearer its tip.

Ceratogloflus arifes from the horn of the gs hy-
©ides, and is laterally inferted into the tongue
near its root, to pull it downward and forward.

StylogloiTus arifes from the extremis of the.
procefTus flyliformis, and is inferted into . tongue
near the former to pull it up and bz vard. I
have very often found another ftyloid mufc I . r o in-
ferted, that I cannot tell whether to call it a m
pf the tongue or pharynx.

The

So Of the M USGLES.

The tongue is a mufcle made of fibres, lon-
gitudinal, circular, and tranfverfe, fo intermixed as
beft to ferve its feveral motions

Hypothyroideus or Ceratothyroideus, arifes
from part of the bans, and the horn of the os hy-
oides, and is infcrted into the lower part of the
cartilago thyroides, to pull it forward.

Sternothyroideus arifes from the infide of the
fternum, and is inferted with the former ; it pulls
the thyroid cartilage directly downward.

Cricothyroidcus arifes from the anterior part
of the cartilago cricoides, and running obliquely up-
ward and outward, is foon inferted into the infide
of the cartilago thyroides, which it pulls towards
the cartilago cricoides. Both this mufcle and its
fellow for the moll: part appear double.

Cricoarytsenoideus pofticus arifes from the back
part of the cartilago cricoides, and is inferted into
the arytasnoides. to pull it backward.

Cricoarytsenoideus lateralis arifes laterally from
the cartilago cricoides, and is inferted laterally into
the arytasnpides. This, with its fellow, pull down
each cartilage toward their origin, and thereby
d'late tlie rimula.

Tlryroarytaenoideus arifes from the fuperior,

middle, aftd inner part of the cartilago thyroides,

is inferted with the former into the ary-

ttcnoide; cartilage to dilate the rimula. Thefe

two.Lil defcribed mufcles are not naturally divided,

>re ought to be accounted but one mufcle.

Arytsenoideus

Of the MUSCLES. 8i

Arytsenoideus is one Tingle mufcle, which arifes
from one arytsenoidal cartilage, and is inferted in-
to the other, to draw them together, and clofe the
rimula. Thefe few fmall mufcles of the tongue
and larynx, with only one pipe, make a great va-
riety of notes and founds that can be made by ar-
tificial inftruments, and that in a manner fo little
underftood by us, and by organs fo little differing
from thofe in quadrupeds, that, for aught we know
of them, brutes might be as capable of all thefc
founds as men.

Stylopharyngseus arifes from near the bottom
of the proceffus ftyloides of the os petrofum,
and running obliquely downward, is infert-
ed into the pharynx. This mufcle, with its
fellow, pulls up and dilates the pharynx to receive
the aliment.

CEfophageus arifes like a wing from feveral
parts of the fcull, tongue, os hyoides, the cricoid
and thyroid cartilages, and is inferted into the
pharynx. This, with its fellow, conflringes the
pharynx, and preffes the aliment down the gullet.

Mufculus vaginalis guise is the mufcular coat
of the gula.

Pterygopharyngscus is not a diftindt mufcle,
but the beginning of the pharynx near the pro-
ceffus pterygoides of the fphenoidal bone.

Pterygoftaphylinus internus arifes from the
os fphenoides, near the iter ad palatum, or
euilachian tube, and is inferted into the uvula,

which

Si Of the MUSCLES.

which it pulls up while we breathe through the
mouth, or fwallow.

Pterygo-ftaphylinus externus arifes by the
fide of the laft defcribed mufcle, and is alfo in-
ferted near it ; but becomes its antagonift by be-
ing reflected on a pully, over a procefs at the
lower part of the pterygoidal proceffes of the fphe-
noidal bone.

Gloflb-ftaphylinus is a very fmali portion of
mufcular fibres, which pafs from the tongue t®
the palate, which it pulls down when we breathe
through the nofe.

The palate itfelf is a fort of double mufcle,
whole action feems only to fupport itfelf, and afiift
thofe mufclcs which pull it upwards.

Digaftricus arifes from finus of the mammil-
lary procefs of the cs temporis, and, from a flelhy
belly becoming a round tendon, paifes through,
and fometimes under, the ftylohyoideus mufcle ;
and then, being tied down by a ligament to the os
hyoides, grows flelhy, and is fo inferted into the
anterior part of the lower jaw internally. This
mufcle' s direction being altered by its being tied to
the os hyoides, where it makes an angle, and not
at its paffage through the ftylohyoideus, pulls the
lower jaw downward with much greater force
than otherwife it could have done ; and being con-
nected to the os hyoides, when it acts, it prevents
the action of feveral mufcles which are concerned
in fwallowing ; whence it is that we cannot fwal-
low

Or the M U S C L E S. 83

low at the fame* time that we open the jaw, as
thofe brutes can whofe digaftric mufcles are not
connected to that bone.

Temporalis arifes from the cs frontis, parie-
tale, fphenoides, malas, and temporis, and, paffmg
under the two proceffes named os jugale, is inferred
externally into the proceflus coronalis of the lower
jaw, which it pulls upward. This mufcle is cov-
ered with a ftrong tendinous fafcia.

MafTeter arifes from the lower edge of the
os malse or zygoma, and the procefs which joins
this from the temporal bone, and is inferted into the
outer part of the angle of the lower jaw, which it
pulls up and forward. Thefe two laft defcribed
mufcles having different directions, when they act
together, make a fteddy motion in the diagonal of
their directions.

Pterygoideus internus arifes from the pro-
ceffus pterygoideus externus, and from the fmus
between the pterygoid proceffes, and is inferted
internally into the angle of the lower jaw, which
it pulls upward.

Pterygoideus externus arifes from the os max-
illare and os fphenoides, near the root of the exter-
nal pterygoid procefs, and is inferted internally
into the proceflus condyloides of the lower jaw,
which it pulls to one fide, and forwards, or acting
with its fellow pulls the jaw directly forward.

Subclavius arifes from the fuperior part of the
firft rib, and is inferted into more than half the

underfide

84 Of the MUSCLES.

underfide of the clavicula next the fcapula. Its life
is to draw the clavicula toward the fternum, that
they may not be fevered in the motions of the
fcapula.

Trapezius arifes from the os occipitis, and
from a linea alba colli, from the fpinal procefs of
the laft vertebra of the neck, and the ten upper-
moil of the back, and from a linea alba between
all thefe proceffes ; and is inferted into one third of
the clavicle next the fcapula, almoft all the back
part of the fpine of the fcapula, and as much of
the proceffus acromion as lies between the fpine of
the fcapula and the clavicle. This mufcle draws
the fcapula directly backward.

It is generally laid by authors, that the feveral
parts of this mufcle, acl: at different times, and fo
pull the fcapula different ways, as obliquely up-
ward, downward, or backward ; but, I think, if
that happened, it muft neceffarily divide this muf-
cle into diftinet portions, thofe that contract always
feparating from thofe that do not.

Rhomboides arifes tendinous under the former
from the fpinal procefs of the inferior vertebra of
the neck, part of the linea alba colli, and from the
•fpinal proceffes of the four or five uppcrmoft ver-
tebra of the thorax, and is inferted into the bafis
of the fcapula, which it pulls up and backward.
The upper part of this mufcle arifmg from the
neck, is, in many bodies, by the motions of the
neck, feparated and made a diflinct mufcle.

Elevator

Of the MUSCLES. $5

Elevator fcapulse arifes from the tranfverfe
proceffes cf the four fuperior vertebras of the
neck, and is inferted into the upper angle of the
fcapula.

Serratus minor anticus arifes under the pe&o-
ralis, from the third, fourth, and fifth ribs, and
is inferted into the proceffus eoracoides fcapu-
lae, which it pulls forward and downward. This
mufcle is always faid to be an elevator of the rib9,
though it arifes from the fcapula, which is fup-
ported by the ribs.

Serratus major anticus arifes from the anterior
part of the eight fuperior ribs, and is inferted
into the bafis of the fcapula* which it draws for-
ward, and by that means moves the focket of the
fcapula upward. This mufcle has been always
accounted an elevator coftarum, though each por-
tion of it is nearly parallel to the rib it rifes from.
All the mufcles inferted into the bafis of the
fcapula are alfo inferted into one another.

Pecloralis arifes from near two thirds of the
clavicula, next the fternum, and all the length of
the os pectoris, and from the cartilages of the ribs,
and is inferted into the os humeri, between the bi-
ceps and the infertion of the deltoides. The ufe of
it is to draw the arm forward. A fmall portion of
the lower part of this mufcle is often confounded
with the cbliquus defcendens abdominis ; and in
fome bodies, neither the upper part, nor its tendon,
can be eafily feparated from the deltoides ; and in

others,

$6 Or the MUSCLE S.

others, even that part of it that arifes from the
clavicula is a diftinct portion. Near the infertion
of this mufcle the fibres crofs thofe from below,
ending above in the arm, and thofe from above
below, that the tendon of this mufcle might not
lie inconveniently low between the arm and thorax,
as it would have done had the fibres which arife
loweft from the fternum been inferted lowed in the
arm ; but this crofTing does not make the tendon
at all ftronger, as is often faid ; nor can I fee how
it came to be thought that this tendon mould want
more ftrcngth in proportion than other tendons.

Deltoides arifes exactly oppofite to the infer-
tion of the trapezius, from one third part of the
clavicula, from the acromion and,fpine of the fca-
pula, and is inferted tendinous near the middle of
the os humeri, which bone it lifts directly upward.
The outermoft parts of this mufcle, when the arm
hangs ddwfi, lie below the centre of motion of the
joint, and therefore can have no lhare in lifting the
humerus up, till it is raifed part of the way by the
other part of this mufcle, and the following mufcle ;
and as the outer parts of this mufcle begin to act,
the following mufcle acts with lefs advantage :
and it feems to me, that the fole reafon why this
mufcle is made of fo many parts, is, that they
may act independently ; for it is demonftrable, that
this mufcle, when the v/hole of it acts, cannot raife
the arm with fo great advantage as a right lined
mufcle of the fame magnitude would have done.

Suprafpinatu$

Of the MUSCLES. S 7

Suprafpinatus arifes from the dorfum fcapula?
above the fpine, and palling between the two pro-
cefTes, is inferted into the upper part of the os hu-
meri, which it helps to raife until it becomes par-
allel with the fpina fcapulae.

The fuprafpinatus, the deltoides, and coracobra-
chial aflift in all the motions of the humerus except
depreffion ; it being necefTary that the arm mould
be raifed and fuftained, in order to move it to any
fide.

Infrafpinatus arifes from the dorfum fcapulat
below the fpine, and is inferted, wrapping over
part of it, at the fide of the head of the os humeri ;
it turns the arm fupine and backward ; for there is
a prone and fupine rotatory motion of the hume-
rus of near ninety degrees.

Teres minor is a fmall mufcle arifmg below
the former from the inferior cofta fcapulse, and is
inferted together with it. It afiifts the former in
turning the arm fupine, but pulls it more down-
wards.

Teres major arifes from the lower angle of the
fcapula, and is inferted at the under part of the or
humeri, about three fingers breadth from the head.
This draws the os humeri toward the lower angle
of the fcapula, and turns the arm prone and back-
ward.

Latiflirmis dorfi arifes by a flat tendon from
the fpinal proceffes of the feven or eight inferior
vertebra? of the back, and thofe of the loins, fa-

crura.

88 Of the MUSCLES.

crum, and ilium : and growing flefhy, after it has
pafTed the extenfors of the trunk, receives another
fmall flefhy beginning from the ninth, tenth, and
eleventh ribs, and is inferted into the os humeri,
with the former. This turns the arm backward,
and prone. The tendon of this mufcle ferves for
a membrane to the extenfcrs of the back, and is
conne&ed to the tranfoerfc proceffes of the verte-
bras lumborum.

Subfcapularis arifes from the hollow fide of
the fcapula, which it fills up, and is inferted in-
to the head of the os humeri, wrapping fome-
what over it. This pulls the arm to the fide and
prone.

Coracobrachial arifes from the procerus cora-
coides fcapulae, in common with the origin of one
head of the biceps, and is inferted into the cs hu-
meri internally about its middle. This raifes the
arm, and turns it fomewhat outward.

Biceps cubiti flexor arifes with two heads,
that the fibres of this mufcle might not comprefs
one another, one from the procefTus coracoides fca-
pulse, in common with the coracobrachialis muf-
cle, and the other by a round tendon from the edge
of the acetabulum fcapula?, which palling in a ful-
cus of the os humeri, afterward becomes flefhy,
and joins the firft head to be inferted with it into
the tubercle of the radius ; and fometimes this
mufcle has a third head, which arifes from the
(middle of the os humeri. This mufcle lifts up the

humc-

Of the MUSCLES. 89

humerus, bends the cubit, and has as great a mare
as any one mufcle in turning the cubit lupine ; the
humerus being fixed by other mufcles, the whole
force of this mufcle will be exerted upon the cu-
bit ; or the cubit being fixed by an extenfor, the
whole force of it will be fpent in raifing the arm,
and therefore ought to be always reckoned among
thofe that raife a weight at arms length. A punc-
ture of the tendinous expanfion of this mufcle is
fuppofed to be always attended with grievous pain
and inflammation, and has, if we have not mif-
taken the caufe, often proved mortal ; yet many
eminent furgeons have given inftances of larger
tendons being cut and ftitched, without any bad
fymptoms ; and we have often feen them cut,
torn, ulcerated, and mortified, without any more
fign of pain than in other parts. So that I can-
not fee what the great mifchief of pricking this
tendinous fafcia is owing to, unlefs its lying fo
much upon the ftretch, which may be wholly
avoided by bending the elbow, and turnino- the
cubit prone. Since I have confidered this cafe,
I have met with one who was thus injured by
an injudicious blood-letter, who ordered the pa-
tient to keep her arm extended for fear of a con-
traction, and fhe was not without the moft violent
pain for a whole fortnight ; but upon bending the
cubit, and turning the arm prone, fhe grew pref-
ently eafy, and, in a few days, well. Neverthe-
lefs, I am perfuaded, that moft of the accidents
G which

yo Of the MUSCLES.

which are thought to be merely from blood-let-
ting, are critical difcharges of fomc difeafe, and
from the puncture a fmall inflammation begin-
ning, increafes and fuppurates. But however lin-
gular I may be thought in this opinion, I can be
fure I am difinterefted in it, having never had any
ill accident follow blood-letting in my life.

Brachiaeus internus arifes from below the mid-
dle of the os humeri, and is inferted into a rough
place of the ulna, immediately below the junc-
ture. This affo bends the cubit.

Supinator radii longus arifes from the lower
and outer part of the os humeri, and is infert-
ed into the upper fide of the radius, near the
carpus. This mufcle is not a fupinator but a
bender of the cubit, and that with a longer lev-
er than either of the two former mufcles, and
is lefs concerned in turning the cubit fupine,
than either the extenfors of the carpus, fingers,
or thumb.

Triceps extenfor cubiti, commonly diftin-
guifhed into biceps and brachiaeus externus. The
firft of thefe heads arifes from the lower cofta of
the fcapula near the acetabulum ; the fecond from
the outer and back part of the os humeri ; the
third, lower and more internal ; and are inferted
into the procerus olecranon of the ulna. The
iirft of thefe heads draws the arm backward, with
as long a lever as it extends the cubit.

A neon x u&

Of the MUSCLES. *t

Anconeus arifes from the outward extuberance
of the os humeri, and is inferted into the upper
part of the ulna : this is alfo an extenfor.

Palmaris longus arifes fmall from the inner extu-
berance of the os humeri, arid from a fhort belly foon
becomes a tendon, which is connected to the lig-
amentum tranfverfale carpi, and expanded in the
palm of the hand. This mufcle is often wanting,
but the expanfion in the hand never ; yet it being
connected to the ligament of the carpus, it muft
bend the carpus, and cannot confined the palm of
the hand ; and when it is wanting, the flexor car-
pi radialis is larger.

Palmaris brevis, or caro quadrata, arifes obfeure-
ly from the ligamentum tranfverfale carpi, and
feems to be inferted into the eighth bone of the car-
pus, and the metacarpal bone of the little finger.
This helps to conftrict the palm of the hand, and is
very different in lize in different bodies.

Flexor carpi radialis arifes from the inner extube-
rance of the os humeri, and foon becoming a ftrong
tendon, paffes through a channel of the fifth bone
of the carpus, and is inferted into the metacarpal
bone of the fore-finger. This not only bends the
carpus upon the radius, but alfo the bones of the
fecond order upon thofe of the firft ; which mo-
tion is nearly as much as that upon the radius.

Flexor carpi ulnaris arifes from the fame extu-
berance with the former, and a fafcia betwixt this
mufcle and the tenfor ulnaris contiguous to the
G 2 ulna,

92 Of the MUS C L E S.

ulna, and is inferted by a fhort tendon into the
fourth bone of the carpus.

Extenfores carpi radiates ; the fiift arifes from
the os humeri, immediately below the fupinator
radii longus, and is inferted into the metacarpal
bone of the firft finger ; the fecond arifes immedi-
ately below this, from the outer extuberance of the
os humeri, and is inferted into the metacarpal bone
of the fecond finger. The firft of thefe mufcles is
a bender of the cubit, as well as an extenfor of the
carpus, and its often acting with the benders of the
cubit while the other is not in a&ion, is the rea-
fon why it is fo diftincl: from it.

Extenfor ulnaris arifes from the fame extube-
rance with the former, and half the ulna below the
anconeus mufcle ; then becoming a tendon, runs
in a fmall finus at the bottom of the ulna, and is
inferted into the metacarpal bone of the little fin-
ger. See Ulna, p. 31,32. The extenfors of the
carpus being inferted into the metacarpus, at once
perform the motion between the bones of the car-
pus, and that between the carpus and radius. The
flexor and tenfor ulnaris acting together turn the
hand downward, the tenfor aud flexor radialis up-
ward.

Perforatus, or flexor fecundi internodii dig-
itorum, arifes from the inner tubercle of the
os humeri, and from the upper part of the
ulna, and the middle of the radius ; then becom-
ing four ftrong tendons, pafles under the ligamen-

tum

Of the MUSCLES. 93

turn tranfverfale carpi, and is inferted into the be-
ginning of the fecond bone of each finger.

Perforans, or flexor tertii internodii digitorum,
arifes from half the ulna, and a great part
of the ligament between the ulna and radius,
then becoming four tendons, paffes under the liga-
mentum tranfverfale carpi, and through ten-
dons of the former mufcle to their infertion into the
third bone of each finger. The tendons of both
thefe mufcles are tied down to the fingers by a
ftrong ligament. If thefe mufcles had not pafTed
one through the other, the perforatus, which is
the leffer mufcle, muft have gone to the laft joint
where the ftronger mufcle is wanted ; and, befides,
the tendons of the fecond joints would have preifed
thofe that bend the laft, and not lain firmly upon
them neither.

Lumbricales, or flexores primi internodii
digitorum, arife from the tendons of the laft
mentioned mufcle, and are inferted laterally to-
ward the thumb into the beginning of the firft
bone of each finger.

Extenfor digitorum communis arifes from
the outer extuberance of the os humeri, and pafling
under a ligament at the wrift, is divided into four
tendons, which communicate upon the firft joint,
which keeps them from Aiding off the joints of
the fingers, where they are a little connected to the
firft bones, and afterward are inferted into the be-
ginning of the fecond bone of each finger.

Extenfor

Or the M-USCL ES.

Extenfor auricularis, or minimi digiti is a por-?
tion of the laft mufcle patting under the ligament
in a diftinct channel.

Extenfor indicis arifes from the middle of the
ulna, and patting under the ligament of the car-
pus, is inferted with the extenfor communis into
the fore-finger. This mufcle extends the fore-fin-
ger fingly. I have twice feen it wanting.

Abductor primi digiti, interoifei, and abductor
minimi digiti, are eight mufcles, one for each
fide of each finger. Abductor primi digiti
arifes from the firft bone of the thumb, and the
fide of the metacarpal bone of the firft finger.
The interoffei are three pair, fitly divided into
external and internal ; the external arife from
the metacarpal bones, whofe fpaces they fill up
next the back of the hand 5 the internal arife
from the fame bones, in the infide of the hand.
Abductor minimi digiti arifes from the tranf-
verfe ligament, and fourth bone of the carpus 5
thefe mufcles are inferted, two into the firft joint
of each finger, and then patting obliquely over
the tops of the fingers, are inferted into their laft
bones ; they bend the firft joints, and extend the
two laft, as in holding a pen, and in playing upon
fome mufical inftruments. The abductors of the
fore and little fingers, with the fecond and fifth
interoffei mufcles acting, the fingers are divari-
cated, and the other four acting bring them to-
gether, and thefe mufcles which divaricate the

fingers.

Of the MUSCLES. 95

fingers, being extenders of the fecond and third
joints, we never can divaricate them without ex-
tending them a little.

AdductorofTis metacarpiminimi digiti arifes from
the eighth bone and tranfverfe ligament of the
carpus, and is inferted into the metacarpal bone
of the little finger, which it pulls toward the thumb
to conftrid the palm of the hand.

Extenfor primi internodii pollicis arifes from
the ulna below the anconeus mufcle, and the lig-
ament between the ulna and radius ; then becom-
ing two, three, or four tendons, is inferted into
the fifth bone of the carpus, and firft of the
thumb. The firft of thefe infertions can only af-
fift the bending of the wrift upward, and in turn-
ing the arm fupine.

Extenfor fecundi internodii pollicis arifes im-
mediately below the former from the radius and
tranfverfe ligament, and is inferted by a few fi-
bres into the fecond bone of the thumb, but chief-
ly into the third.

Extenfor tertii internodii pollicis arifes im-
mediately below the laft defcribed, from the ul-
na and ligament, and paffes over the radius near-
er the ulna, to be inferted at the third bone of the %
thumb. This extends the thumb more toward
the ulna than the former mufcle, and is very much
a uipinator.

Flexor primi et fecundi oflis pollicis arifes
irom the fifth bone and tranfverfe ligament

of

9 6 Of the MUSCLES.

of the carpus, and from the beginnings of the two
firit. metacarpal bones, and is inierted into the
whole length of the firft bone of the thumb, and
tendinous into the beginning of the fecond ; the
fcfamoid bones of the thumb in fuch bodies as
have them, lie in this tendon, where it paffes over
the joint.

Flexor tertii internodii pollicis arifes large
from almoft all the upper part of the radius,
and becoming a round tendon, pafTes under the
ligamentum tranfverfale carpi, to be inferted into
the third bone of the thumb. This mufcle fingly
acting, draw r s the thumb towards the metacarpal
bone of the little finger ; but the laft mentioned
mufcle acting with it ? turns it toward the fore-
finger.

Adductor pollicis arifes from the carpus,
and almoft the whole length of the metacarpal bone
of the long finger, and is inferted into the begin-
ning of the fecond bone of the thumb. This muf-
cle naturally enough divides into two, and might
better be called a flexor than adductor.

Abductor pollicis arifes from the fifth bone
and ligamentum tranfverfale of the carpus, and
is inferted laterally into the beginning of the
fecond bone of the thumb, to draw it toward the
radius.

The mufcles which bend the thumb are much
lefs than thofe which bend the fingers ; neverthe-
lefs the thumb is able to refill all the fingers,

merely

Of the M U S C L E S. 97

merely from the advantages that arife from the
thicknefs and ihortnefs of the bones of the thumb,
compared with thofe of the fingers ; but then the
quicknefs of motion in the fingers will exceed that
of the thumb, as much as the fingers exceed the
thumb in length, and their mufcles thofe of the
thumb in largenefs.

Supinator radii brevis arifes from the outer
extuberance of the os humeri and upper part of
the ulna, and running half round the radius, is in-
ferted near its turbercle.

Pronator teres arifes from the inner apo-
phyfis of the os humeri, and upper and fore-part of
the ulna, and is inferted tendinous into the radius
below the former.

Pronator quadratus arifes from the lower
edge of the ulna, near the carpus, and paffing under
the flexors of the fingers is inferted into the radius.

Thefe mufcles are occafionally affifted in their
actions by the mufcles of the hands, the extenfors
affifting the fupinators, and the flexors the prona-
tors, and molt of the extenfors of the hand take a
great part of their origin from the tendinous fafcia
that covers them.

Maftoideus arifes tendinous from the fternum
near the clavicula, and by a feparate fleihy por-
tion from the clavicula, which foon unites with
the other beginning, and is inferted into the outer
part of the mammillary procefs of the temporal
bone. It pulls that fide of the head it is inferted

into

9 8 Of the MUSCLES.

into towards the ftemum, and turns the face to-
ward the contrary fhoulder. This, and its fellow,
pull the head and neck toward the brcaft, and act,
with a much longer lever upon each lower verte-
bra, than they do upon the next above, and with
more power upon any of thofe joints than upon
the head. This mufcle being inferted into the
head, beyond the centre of motion of the head
with the firft vertebra, has been fuppofed, by feve-
ral anatomifts, to pull the head backward ; but the
pairing beyond fignifies nothing to that purpofe,
uniefs a line going through its axis would pafs be-
low the centre of motion : and it is the more to be
wondered how this miftake prevailed, if we confider
that this mufcle's being added to the extenfors of
the head and neck, would make the force of that
action a hundred times greater than that of the
benders. And if this is not enough to convince,
let any one lying on his back raife his head, and
he will foon feel this mufcle in action ; but bow-
ing the head forward in an erect pofture will not
ihew this, uniefs fome refiftance is made to the
head, becaufe the centre of gravity of the head ly-
ing before the centre of motion, there needs no
more than a relaxation of the extenfors, to bring
the head forward in that pofture.

Rectus internus major arifes from the anterior
part of the tranfverfe proceffes of the third, fourth
fifth, and fixth cervical vertebrae ; and paffmg
over the two fupcrior, is inferted into a rough-

nefs

Of the M U S C L E S. 99

nefs of the occipital bone near the fore-part of the
great foramen. This bends the head on the two
firft vertebras of the neck.

Rectus minor internus arifes under the laft
mufcle, from the firft vertebra, and is inferted
under it into the os occipitis. This bends the head
on the firft vertebra.

Rectus lateralis arifes from the anterior part of
the tranfverfe procefs of the firft vertebra of the
neck, and is inferted into the os temporis and
occipitis between the mammillary and ftyloid pre-
cedes. This turns the head on one fide.

Splenius arifes by a thin tendon from the fpi~
nal proceffes of the five fuperior vertebrae of the
thorax, and the loweft of the neck, and linea alba
colli, and is inferted into the os occipitis, the up-
per part of the mammillary procefs of the temporal
bone, and the tranfverfe procefies of the three
fuperior cervical vertebrae. This pulls the head
and neck backward, and to the contrary fide ; but
both of thefe acting together pull them directly
backward.

Complexus arifes from the tranfverfe procefies
of the fix or feven fuperior vertebrae of the thorax ;
and fix inferior of the neck, and is inferted into
the os occipitis, and back part of the os temporis ;
this laft part is fometimes diftinct enough to be
accounted another mufcle, It pulls the head and
neck back.

Rectus

ico Of the MUSCLES.

Rectus major pofticus arifes from the fpinal
proceffes of the fecond vertebra of the neck, and
is inferted broader into the os occipitis. It pulls
the head back on the two firft vertebra?.

Rectus minor pofticus arifes from the back
part of the firft vertebra of the neck, it having no
fpinal procefs, and is inferted below the former into
the fame bone, to pull the head back on the firft
vertebra.

Obliquus fuperior arifes from the tranfverfe
procefs of the firft vertebra, and is inferted into the
os occipitis and back part of the os temporis, near
the rectus major ; either of thefe acting, aflift the
rectus lateralis on the fame fide ; but both together
pull the head back.

Obliquus inferior arifes from the fpinal procefs
of the fecond vertebra of the neck, and is in-
ferted into the tranfverfe procefs of the firft.
This, with its fellow, alternately acting, turns the
head with the firft vertebra in a rotatory manner
on the fecond, whofe proceflus dentatus is the axis
of this motion.

Interfpinales colli are three or four pair of
mufcles between the bifid proceffes of the cervi-
cal vertebrae, which they draw nearer each other
when the neck is bent backward.

Longus colli arifes laterally from the bodies
of the four fuperior vertebras of the thorax, and
from the anterior part of the tranfverfe proceffes of
the five inferior vertebrae of the neck, and is in-
ferted

Of the MUSCLES. tot

ferted into the fore-part of the firft and fecond ver-
tebras of the neck, which it bends forward*

Intertranfverfales colli are portions of' flefh
between the tranfverfe proceffes of the verte-
bras of the neck, like the interfpinales, but not fo
diftinct ; they draw thefe proceffes together.

Spinalis colli arifes from the tranfverfe procef-
fes of the five fuperior vertebras of the back, and
is inferted into the fpinal proceffes of the fecond,
third, fourth, and fifth vertebras of the neck. This
pulls the neck backward.

Tranfverfalis colli arifes from the oblique
proceffes of the four inferior vertebras of the
neck, and is inferted into the fpinal procefs of the
fecond vertebra of the neck. This mufcle is but
a continuation of the tranfverfalis or femifpinalis
dorfi.

The mufcles of the head and neck are moft of
them obliquely directed, which makes them per-
form the oblique motions, as well as extenfion and
flexion ; which is highly convenient in this cafe,
becaufe the joints moved by thefe mufcles, being
under the weight moved, it is neeeffary that the
head mould be kept fteady by the extenfors, and
flexors too, when any great weight is upon the
head ; and thefe mufcles, from the obliquity of
their directions, not only perform thefe two actions
at once, but acting by pairs they move the head
and neck fteadily, in a diagonal direction, which
ftrait mufcles could not have done fo well.

Scalenus

102 Of the MUSCLES.

Scalenus arifes from the tranfverfe proceffes
of the fecond, third, fourth, fifth and fixth cervi-
cal vertebra. It is inferted, in three parts, into
the two uppermoft ribs, being thus divided for the
tranfmimon of the fubelavian veffels. This muf-
cle may bend the neck ; but its chief ufe is to fup-
port the upper ribs, which is necefTary to deter-
mine the contraction of the intercoftal mufcles
that way, and a ligament could not have done
this, becaufe of the various pofitions that the neck
and back are liable to.

Serratus fuperior pofticus arifes with a thin
tendon, infeparable from the rhomboides, from
the fpinal procefs of the inferior cervical vertebra,
and the three fuperior of the thorax, and is in-
ferted into the fecond, third, and fourth ribs, im-
mediately beyond their bendings ; this, with the
fcalemis, fuftains the upper ribs, that they might
not be pulled downward by the deprefTors of
the ribs in exfpiration, as the lower ribs are up-
ward in inspiration.

Serratus inferior pofticus arifes with a broad
tendon, infeparable from that of the lathTimus
dorfi, from the fpinal proceifes of the three fupe-
rior vertebrae of the loins, and two inferior of
the thorax, and is inferted into the tenth rib, but
chiefly the ninth and eleventh : it pulls down the
ribs in exfpiration,

Intercoftales are eleven pair on each fide,
in the interftices of the ribs ; from their fituations

diftinguiftied

Of the MUSCLES. 103

diftinguifhed into the external and internal ; they all
arife from the under edge of each rib, and are in-
ferted into the upper edge of the rib below. The
external are largeft backward, having their firft
beginnings from the tranfverfe procefles of the ver-
tebrae, like diftin£t mufcles, which fome call leva-
tores coftarum. The internal run all from above
obliquely backward ; being thickeft forward, and
thinner! toward the fpine. Thefe are alfo continu-
ed betwixt the cartilages of the fternum, with fi-
bres perpendicular to the cartilages ; and between
the cartilages of the loweft ribs, they are infepa-
rable from the obliquus afcendens abdominis.
Thefe mufcles, by drawing the ribs nearer to each
other, pull them all upward, and dilate the tho-
rax, they being fuftained at the top by the fcale-
nus and ferratus fuperior pofticus. To thefe Mr.
Cowper adds fome flelhy fibres, which run from
one rib over a fecond to a third, near the fpine,
which are levatores coftarum.

Triangularis flerni arifes internally from the
cartilago enfiformis, and the lower edge of the os
pectoris, and is inferted into the end of the third,
fourth, fifth and fixth ribs. This pulls the ribs
to the bone of the fternum, and thereby bends its
cartilages in exfpiration.

Diaphragma arifes, en the right fide, by a pro-
cefs from three lumbal vertebrae, and one of the
thorax ; and on the left, from the one fuperior of
the loins, and inferior of the thorax ; this laft part

beinc:

io4 Of the MUSCLES.

being lefs to give way to the great artery, and is
inferted into the lower part of the fternum and the
five inferior ribs. The middle of this mufcle is a
flat tendon, from whence the flefhy fibres begin
and are diftributed, like radii, from a centre to a
circumference. When this mufcle acts alone, it
ccnftricts the thorax, and pulls the ribs downward,
and approaches toward a plane ; which action is
generally performed to promote the ejection of the
feces. In large infpirations, when the intercoftals
lift up the ribs to widen the thorax, this mufcle
acts enough to bring itfelf toward a plane, without
overcoming the force of the intercoftals, by which
means the breaft is at once widened and lengthen-
ed : when it ads with the abdominal mufcles, it
draws the ribs nearer together, and conftricts the
thorax, and the fuperior force of the abdominal
mufcles thrufling the parts of the lower belly againft
it, it becomes at the fame time convex upward,
and fhortens the thorax, which occafions the largeft
exfpirations ; or acting alternately with the abdo-
minal mufcles only, a more moderate infpiration
and exfpiration is made by fhortening and lengthen-
ing the thorax only, which is what we chiefly do
when lying down ; or acting alternately with the
intercoftals only, a moderate exfpiration and infpi-
ration is caufed, by the widening and narrowing the
breaft, which is what we are moft prone to in an
erect pofition, the mufcles of the abdomen at fuch
times being employed in fupporting the parts con-
tained

Of the MUSCLES. 105

tained in the abdomen. And though thefe mo-
tions of the ribs require at any one time but very
little force, the air within the thorax balancing that
without ; yet that thefe mufcles, whofe motions are
efTential to life, may be never weary, the infpirators
in moft men have force fufficient to raife mercury
in a tube four or five and twenty inches in an
erect pofture, and the exfpirators fix or feven ; the
firft of which will require about four thoufand
pound force in moft men, and the other propor-
tional. But I imagine, that lying down, thefe pro-
portions will differ by the weight of the parts con-
tained in the abdomen. In all the bodies I have
diffected, I have found the diaphragm convex up-
ward, which gave me occafion to think, that all
animals died in exfpiration ; till the forementioned
experiment difcovered, that the mufcles of infpira-
tion were ftronger than thofe of exfpiration ; which
led me to make the following experiment. I cut
the wind-pipe of a dog, and having a firing ready-
fixed, I put a cork into it, and tied it fall inftantly
after infpiration ; upon which I obferved, that the
diaphragm, and the other mufcles of infpiration and
exfpiration, were alternately contracted and diftend-
ed for fome time ; but when he was dead, the ab-
dominal mufcles were in a ftate of contraction, the
ribs were elevated to dilate the thorax, and the
diaphragm was convex upward. This experiment
alfo fliews, that the diaphragm is not a mufcle of
equal force either to the depreflbrs or elevators of

H the

106 Of the MUSCLE S.

the ribs, it neither hindering the elevators from
railing the breaft ; nor the depreflbrs from thruft-
ing it upward, by compreffing the parts contained
in the abdomen, though the breaft was full of
air.

Sacer facrolumbalis, longiffimus dorfi, and
femiipinalis, are all that portion of flcfh be-
ttfixt the os facrum and the neck, which feeing
tkd e is no membrane to diftinguifh it into feveral
nuilcles, and that it is all employed in the fame
a&ions, I mail gisre it the name of extenfor dorfi
et lumborum, and deferibe it all as one mufcle.

Extenfor dorfi et lumborum arifes from the
upper part of the os facrum, the fpine of the os
ilium, the back parts of the lowermoft vertebras
of the loins, and remarkably from thefe ftrong ten-
dons which appear on their outfides. That part of
this mufcle, which is known by the name of facro-
lumbalis, is inferted into all the ribs near their ar-
ticulations, with the tranfverfe proceffes of the ver-
tebra:, and into the tranfverfe procefs of the laft
vertebra of the neck ; befides, as this parTes over
tire ribs, it receives an origin from every rib, in a
manner that cannot well be defcribed. The por-
tions of this mufcle, which arife from the ribs, and
are inferted into the other ribs above, will neceffarily
, draw the back part of the ribs nearer together, which
rnufl always be done as the back extends, and in-
dependent of other actions of the thorax. The next
portion of this mufcle, called iongiflimus dorfi,

ft

Of the MUSCLES. io

is inferted into all the tranfverfe procefles of the
Vertebrae of the back, and partly into the ribs, and
the uppermoft tranfverfe proceffes of the vertebras
of the loins ; and the upper end of it is neither
very diftinct from the cornplexus of the head, nor
fpinalis of the neck. The reft of this mufcle,
known by the names of femifpinalis, facer, &c.
arifes alfo from all the tranfverfe and oblique pre-
cedes of the loins and back ; every portion, except
the lowcnnoit, paffing over five joints, is inferted
into the fpina! procefs of the fixth vertebra above
its origin, all the way up the back, and at the
neck commences tranfverfalis colli. This paffing
of each portion of a mufcle over a few joints, dis-
tributes their force equally enough among all thefe
joints, without the fibres being directed more ob-
liquely than thofe of penniform mufcles ; but the
neck and loins not having fufficient provifion of
this fort, there are fmall mufcles between their pro-
ceifes, which, though tb 4 ey are of little importance
for the motions of thofe parts, yet are fufficient to
diftribute the force of larger mufcles equally
among thofe joints ; and, befides the ufes of the
extenfor dorfi et lumborum, which its name im-
plies, it and its fellow alternately raife the hips in
walking, which any one may feel by laying his
hand upon his back.

Quadratus lumborum arifes from the upper
part of the fpine of the ilium, and is inferted in-
to all the tranfverfe procefles of the four upper-
H 2 moft

10S Of the MUSCLES.

mofl lumbal vertebrae. This, and its fellow, act-
ing alternately, affift the laft mentioned mufcle in
raifing the offa innominata in progreffion : or each
acting iingly, while the lower limbs are not moved,
inclines the body to one fide.

Intertranfverfales lumborum are fmall muf-
cles feated between all the tranfverfe proceffes of
the vertebrae lumborum, to bring them nearer to-
gether.

Pfoas parvus arifes laterally from the body of
the firft lumbal vertebra, and the loweft of the
back, and foon becoming a fmall tendon, is inferted
into the os pubis, near the ilium. It either affifts
in bending the loins forward, or raifing the os in-
nominatum in progrelhve motions. This mufcle
is often wanting.

Pfoas magnus arifes laterally from the bodies
and tranfverfe proceffes of the four fuperior ver-
tebrae of the loins, and the laft of the back, and is
inferted, with the following mufcle, into the leffer
trochanter. This bends the thigh, and when the
pfoas parvus is wanting, this is larger.

Iliacus internus arifes from the concave part
of the ilium, and from its lower edge, and pairing
over the ilium, near the os pubis, joins the former
mufcle, and is inferted with it, to be employed in
the fame action.

Pectineus arifes from the os pubis or pectinis,
near the joining of that bone with its fellow, and
is inferted into the linea afpera of the thigh bone,

four

Of the MUSCLES. 109

four fingers breadth below thcleffer trochanter.
This bends the thigh, and turns the toes outward.

Triceps femoris. The two leffer heads of
this mufcle arife under the peclineus, and the third
from the inferior edges and back part of the os
pubis and ifchium, and is inferted into the whole
length of the linea afpera and the inner .apophysis
of the os femoris. This alfo bends the thigh, and
turns the toes outward. When the thigh bone is
moved in a plane, which cuts at right angles a plane
that paffes through the axis of either head of the
laft mufcle, that head rifing lower than the centre
of motion of the hip joint, it will either affift the
flexors or extenfors, and that moft when the
bone has been moved moll backward or forward :
and as either of thefe heads lie more or lefs out
of the faid plane, they will give greater afiiftance
to that motion which is made on the fide of the
faid plane, contrary to their fituation, and lefs on
the fame fide. This mechanifm is frequently
made ufe of to make one mufcle ferve different
actions ; but I have only explained it in this in-
ftance, becaufe it is the moft confiderable one that
I know.

Cluteus maximus arifes from the back part
of the fpine of the ilium, and the dorfum ilii, and
fide of the os coccygis and facrum, and a ligament
extended between thefe bones, and from a thin
fafcia, fpread over that part of the following
mufcle which this does not cover, and is inferted

no Of the MUSCLES.

by a ftrong tendon into the upper part of the lincst
afpera of the thigh bone, and alfo into the flat ten-
don of the fafcialis mufcle, which infertion into, or
connexion with, that tendon, raifes this mufcle
farther from the centre of motion, and increafes its
ftrength. This extends the thigh, and both thefc
together being contracted, occasionally affift the
levatores ani in fupporting the anus. The breadth
of the origin and infertion of this mufcle is very
obfervable ; for by that means, though it is the
largeft mufcle in the body, it is neverthelefs ;ht-»
lined, without one fibre compremng another any
more than in penniform mufcles.

Gluteus medius arifes from all the anterior
part of the fpina and dorfum ilii, and under part
cf the laft mentioned mufcle, and is inferted into
the upper part of the great trochanter of the thigh
bone. This extends the thigh outward.

Gluteus minimus arifes entirely under the
former, from the dorfum ilii, and is inferted into
the upper and anterior part of the great trochanter
and neck of the thigh bone to extend the thigh.

Pyriformis arifes internally from the infide
of the os facrum, and growing, in more than half
its progrefs, into a round tendon, is inferted into the
upper part of the fmus, at the root of the great tro-
chanter. This aflifts fomewhat in extending the
thigh, but more in turning it outward.

Quadratus femoris arifes from the obtufe pro-
cefs of the ifchium, and is inferted into the up-
per

Of the MUSCLES. hi

per part of the linea afpera of the thigh bone, be-
tween the two trochanters. This draws the thigh
inward, and dire&s the toes outward.

Obturator interims or marfupialis arifes gen-
erally from a flrong membrane, cr ligament,
which fills up the hole of the cs innominatum,
and from the circumambient bone; thence pac-
ing over a channel in the ifchium, betwixt its
two proceffes, it receives from them two other
portions, which are a fort of marfupium, and is
infertcd into the fmus of the great trochanter.
This turns the thigh outward.

Obturator externus arifes oppofite to the form-
er, from the outfide of the os innominatum, and
is inferted into the fmus of the great trochan-
ter. This alfo turns the thigh outward. * Thefc
four laft mentioned mufcles acting with the ex-
tenfors, prevent their turning the toes inward, and
in ftepping forwards are continually acting to turn
the toes outwards ; for though the toes are placed
perpendicular to the front of the body, in taking
a long ftep, thefe mufcles bring them perpendic-
ular to the fide of the body ; and as thefe direct,
the fame extenfors will turn the thigh cither out-
ward or backward, with their full force.

Fafcialis, or membranofus, arifes from the
fore-part of the fpine of the ilium, and in about
five inches progrefs becomes a flat tendon, or faf-
cia, which is joined by a confiderable detach-
ment from the tendon of the gluteus maximus,

and

Hi Of the MUSCLES.

and from the linea afpera of the thigh bone, and
then covering in an efpecial manner the vaftus
externus, is inferted at the top of the tibia and
fibula, and then proceeds to join the fafcia, which
covers the upper part of the mufcles fituate on the
outfide of the tibia, and from which a great part
of the fibres of thofe mufcles arife. About the
middle of the leg it grows loofe, and is fo contin-
ued to the top of the foot, being connected there,
and at the lower part of the leg, to the ligaments
which tie down the tendons. This tendon, where
it covers the vaftus externus, receives additional
tranfverfe fibres, which run through the thigh,
but are moil confpicuous on the outfide. This
draws the thigh outward, and pafling over the
knee forwarder than its axis of motion, it will
help to extend that joint.

Gracilis arifes from the os pubis, clofe to the
penis, and is inferted into the tibia, four or five
fingers breadth below the knee. This draws the
thigh inward, and paffing over the knee, behind
its axis of motion, it will help to bend it.

Sartorius arifes from the fore-part of the fpine
of the ilium, and thence defcending obliquely
to the infide of the tibia, is there inferted four or
five fingers breadth below the joint. This at once
helps to bend both the thigh and leg, particularly
the thigh, at very long levers ; it directly helps to
lift up the leg in walking up ftairs, or laying the
legs acrofs, like taylors.

Semitendinofiis

Of the MUSCLES. 113

Semitendinofus arlfes from the obtufe procefs
of the ifchium, and growing a round tendon in
fomewhat more than half its progrefs, is inferted
near the former n\ufcles into the tibia : it helps to
extend the thigh and bend the tibia.

Semimembranofus arifes by a flat tendon like
a membrane from the obtufe procefs of the if-
chium, and being continued tendinous betwixt
the bellies of the laft mentioned and following
mufcles, and then growing flefhy, becomes again
tendinous above the joint, and is inferted nearer the
joint - than the former mufcle for the fame ufe.

Thefe two make the internal hamftring, and
arifing and inferting fo near together, they might
have been one mufcle, but their fibres would have
been near twice as long, which would have given
a motion near twice as quick, but not fo ftrong,
unlefs it had been inferted at a diftance from, the
joint it moves proportionable to its length, which
could not well be ; therefore they are made two
mufcles of a number of fibres nearly equal to what
one could have been, and are inferted at diftances
from the axis of motion of the knee, proportional
to the different lengths of their fibres in the direc-
tions of their axis.

Biceps tibise, the firfb head arifes in common
with the two preceding mufcles, from the obtufe
procefs of the ifchium ; the fecond from the lower
part of the linea afpera of the thigh bone. This
foon joins the former, and is inferted with it into

the

ii4 Of the MUSCLES.

the upper part of the fibula to bend the leg, and
the firft head alfo extends the thigh. The tendon
of this mufcle makes the external hamftring, when
the knee is bent ; and when we fit down, the bi-
ceps will turn the leg and toes outward, and the
femitendinofus and femimembranofus will turn
them inward.

Popliteus arifes from the outer apophyfis of
the os femoris, and thence running obliquely in-
ward, is inferted into the tibia immediately below
its head. This afiifts the flexors, and draws the ti-
bia toward the outer apophyfis of the thigh bone.

Rectus tibiae arifes with a tendon from the
upper part of the acetabulum of the os innomina-
tum, and by another tendon, which is a fort of
ligament to this, from a procefTus innominatus of
the ilium below its fpine forward, and is inferted,
together with the three following mufcles, into the
patella. It bends the thigh, and extends the tibia.

Vaftus externus arifes from the anterior part
of the great trochanter and upper part of the li-
nea afpera of the thigh bone, and is inferted into
the upper and external part of the patella. It ex-
tends the tibia.

Vaftus internus arifes from the inner and
lower part of the linea afpera, and is inferted into
the upper and inner part of the patella, to extend
the tibia ; and the fibres of this mufcle being ob-
lique, it keeps the patella in its place, the other
mufcles lying in the direction of the os femoris,

which

Of the MUSCLES. 115

vphich makes an obtufe angle with the tibia, they
would alone be liable to draw the patella outward.
This contrivance is moil obvious in thofe whofe
knees bend moil inward.

Crureus arifes between the two laft, below the
rectus, from all the convex part of the os femoris,
and is* inferted in like manner into the patella ; the
patella being tied down by a flrong ligament to the
tibia. Thefe three laft mufcles extend the tibia
only, and might very properly be called extenfor
tibia 1 triceps.

'Gafterocnemius arifes by two fmall beginnings
above the back part of the apophyfis of the os
femoris, which foon becoming large bellies unite,
and then become a flat tendon which joins the
following mufcles to be inferted into the os cal-
cis. The two parts of this mufcle are by fomc
writers diftinguifhed into two mufcles. Its ufe is
to extend the tarfus and bend the knee.

Plantaris arifes under the outer beginning of
the laft named mufcle, from the external apophyfis
of the os femoris, and foon becoming a fmall ten-
don, is fo continued betwixt the foregoing and fub-
fequent mufcles, and is inferted with them. It
bends the knee, and extends the tarfus. Authors
derive the tendinous expanfion on the bottom of the
foot from the tendon of this mufcle ; but feeing
the expanfion is much more than this tendon could
make, and that this tendon can be traced no far-
ther than, the os calcis, and that the expanfion is

sis

n6 Of the MUSCL E S.

as large when the mufcle Is wanting, which is not
feldom, I cannot be of that opinion.

Gafterocnemius internus arifes from the up-
per part of the tibia, and one third of the fibu-
la, below the popliteus, and is inferted with the
two foregoing mufcles by a ftrong tendon into the
upper and back part of the os calcis. This mufcle
only extends the tarfus.

Tibialis anticus arifes from the upper and ex-
terior part of the tibia, and is inferted laterally
into the os cuneiforme majus of the tarfus, and by
a fmall portion of its tendon into the metacarpal
bone of the great toe, This bends and turns the
tarfus inward.

Tibialis pofticus arifes nrft by a fmall begin-
ning from the upper part of the tibia between
that bone and the fibula, then pafTmg between
the bones through a perforation in the tranfverfe
ligament which connects thofe bones, it takes other
beginnings from the upper and middle part of the
tibia, and from the middle of the fibula, and the
ligament betwixt the tibia and fibula ; then grow-
ing a rpund tendon, panes under the inner ancle,
and is inferted into the lower part of the os navi-
cular, and into the os cuneiforme majus. This
extends and turns inward the tarfus.

Peroneus longus arifes from the upper and
outer part of the fibula, and growing a tendon to-
ward the lower part of this bone, panes under the
outer ancle, and the mufcles fituated on the bot-
tom

Of the MUSCLES. 117

torn of the foot, and is inferted into the beginning
of the metatarfal bone of the great toe, and the
os cuneiforme next that bone. This turns the
tarfus outward, and directs the force of tlje other
extenfors of the tarfus toward the ball of the great
toe.

Peroneus brevis arifes from the middle of the
fibula, under a part of the former, and growing
tendinous, pafTes under the outward ancle, and is
inferted into the beginning of the upper part of
the os metatarfi of the little toe, and fometimes
beftows a fmall tendon on the little toe. Its ufe
is to extend the tarfus, and turn it outward.

Thefe two laft mufcles riding over the lower
end of the fibula, are often the caufe of a fprain
in the outer ancle, when they are vehemently ex-
erted to fave a fall.

Extenfor pollicis longus arifes from the upper
and middle part of the fibula and the ligamentum
tranfverfale, and foon becoming a ftrong tendon,
is inferted into the laft bone of the great toe.
This alfo bends the tarfus with a much longer
lever than it extends the toe.

Extenfor pollicis brevis arifes from the fore-part
of the os calcis, and is inferted into the fame place
with the former.

Flexor pollicis longus arifes from the fib-
ula, oppofite to the extenfor / longus, and then
pafling under the inner ancle, is inferted into the
under fide of the laft bone of the great toe. This

extends

n8 • Of the MUSCLES.

extends the tarfus at a longer lever than it benda
the toe.

Flexor brcvis and adductor poilicis arc the fame
mufcle, arifing from the two lefler offa cuneiformia
and os cuboides and calcis. They are inferted
into the ofTa fefamoidca, which are tied by a
ligament to the fiflt bone of the great toe, reckon-
ing only two bones to the great toe. Thefe muf-
cles bend the great toe.

Abductor poilicis arifes pretty largely from
the inner and back part of the os calcis, and by
a fmaller beginning from the os navicularc ;
thence palling forward contiguous to the os cu-
neifcrme majus, paries by the external fefamoid
bone of the great toe to its infertion into the lirfb
bone of the great toe. This mufcle is lefs an ab-
ductor than a flexor poilicis pedis ; it alfo very
much helps to conflricl: the foot lengthways.

Tranfverfalis pedis arifes from the lower end of
the metatarfal bone of the toe next the leaft, and
is inferted into the internal fefamoid bone. This
truly is an adductor of the great toe, and helps to
keep the conftri&ure of the bottom of the foot.

Extenfor digitorum pedis longus arifes acute
from the upper part of the tibia, and from the
upper and middle part of the fibula and ligament
between thefe bones ; then dividing into five
tendons, four of them are inferted into the fecond
bone of each lefler toe, and the fifth into the be-
ginning of the metatarfal bone of the leaft toe, and

fometimes

Of the MUSCLES, 116

fometimes by a fmall tendon alfo into the little toe.
This laft portion for the moll part is feparate from
its beginning, and may be accounted a diftinct muf-
cle. The four firft tendons only of this mufcle ex-
tend the toes, but ail five bend the tarfus, and tha"
with a longer lever than any of them bend a toe.

Extenfor digitcrurn brevis, arifes together
with the extenfor pollicis brevis, from the os cal-
cis, and dividing into three fmall tendons is inferr-
ed into the fecond joint of the three toes next
the great one. The long extenfors of the toes fervc
not only to extend them, but alfo contribute to
the bending of the ancle, which motions are ufu-
ally performed together in progrefiion ; but the
fhort extenfors arifing below the ancle, extend th-
roes only ; and when the long extenfors are em-
ployed for that action only, the extenfors of the
tarfus muft act at the fame time, to prevent the
bending of the ancle. This is the reafon why the
toes have need, though their motions are lefs, of
more extenfors than the fingers.

Flexor brevis or perforatus arifes from the
under and back part of the os calcis, thence pann-
ing toward the four leffer toes, divides into four
tendons, which are inferted into the beginning of
the fecond bone of each of the leffer toes. Thefc
tendons are divided to let through the tendons of
the following mufclcs.

Flexor longus or perforans arifes from the
back part of the tibia, above the inferiion of

the

120 5 Of the MUSCLES.

the popliteus, and part of the fibula ; thence de-
fcending under the os calcis to the bottom of the
foot, there becomes tendinous, often croffes, and,
in moft bodies, communicates with the flexor lon-
gus pollicis pedis ; then it divides into four tendons
which pafs through thofe of the flexor brevis, and
are inferted into the third bone of the four leffer
toes. This mufcle alfo extends the tarfus. The
fecond beginning of this mufcle arifes from the os
calcis, and joins the tendons where they divide.
This portion only bends the toes ; and feeing the
flexor longus of the toes will, when it acts alone,
extend the tarfus as well as bend the toes, this
portion, like the fhort extenfors of the toes, feems
purpofely contrived to bend the toes alone.

Lumbricales arife from the tendons of the
perforans, and are inferted into the firfl bone of
each of the leffer toes which they bend.

Abductor minimi digiti pedis arifes by the
perforatus from the os calcis, and being part of
it inferted into the metacarpal bone of the leafl
toe, it receives another beginning from the os cu-
boides, and is inferted into the nrft bone of the leafl
toe, which it bends and pulls outward, and very
much helps to conftrict the bottom of the foot.

Abductor fecundus minimi digiti arifes under
the former mufcle from the metatarfal bone, and is
inferted into the little toe.

Interoffei are feven mufcles which lie like
thofe of the hands, and arife like them from the

metatarfal

Of the MUSCLES. 121

metatarfal bones, and are inferted like them into
the laft joints of the four lefler toes ; and being in
their progrefs attached to the tendons, which ex-
tend the fecond joints of the toes, they will extend
both thefe joints. Thefe mufcles may be fitly dw
vided into external and internal ; the internal alfo
bend the firft joints, as do all the interoffei in the
hand, but here the outer ones extend the firft joints ;
and if we confider that the firft of thefe mufcles is
analogous to the abdudtor indicis of the hand, and
that the abductor minimi is alike in both, we find
that the mufcles to move the fingers and leffer
toes fideways are alike in number, though this mo-
tion of the toes is in a manner loft from the ufe of
fhoes. The mufcles that bend or extend the laft
joints of the toes will alfo move the fecond and
firft, and thofe that move the fecond will alfo
move the firft, as they do in the fingers.

T A B.

( »* )

TAB. XL

2 Mufculus frontalis*

2 Temporalis.

3 Orbicularis.

4 The parotid gland, with its duel, which paffes

through the buccinator.

5 Maftoideus.

6 Zygomaticus.

7 Elevator labii fuperioris proprius.

8 Elevator labiorum communis.

9 Depreflbr labiorum communis.
io Sphincter oris.

1 1 Depreflbr labii inferioris proprius*

12 Buccinator.

13 Sterno-hyoidei.

14 Coraco-hyoideus.

15 Maftoideus.

16 Trapezius.

1 7 Pe&oralis.

18 Deltoides.

TAB.

TAB XT.

( *23 )

TAB. XIL

1 Mufculus maftoideus.

2 Pe&oralis.

3 Biceps flexor cubiti.

4 Coraco-brachialis.

5 Triceps extenfor cubiti.

6 Latiffimus dorfi.

7 Serator major anticus.

8 Obliquus defcendens abdominis*

9 Rectus abdominis.

10 Pyramidalis.

11 Sartorius.

12 Fafcialis.

13 Rectus femoris.

* 2 TAB.

( **'4 )

T A B. xnr.

i Trapezius.

2 Deltoides.

3 Infrafpinatus fcapulae.

4 Teres major.

5 Rhomboides.

6 Latiffimus dorfi.
j Glutaei.

S Obliquus defcendens abdominis.

TAB.

f E\B~xiii

J \JS(4

6

( w )

TAB. XIV.

s Mufculus deltoides.

2 Triceps extenfor cubiti.

3 Anconaeus.

4 Extenfor carpi radialis primus.

5 Extenfor carpi radi alis fecundus.

6 Extenfor carpi ulnaris.

7 Flexor carpi ulnaris.

8 Deltoides.'

9 Biceps flexor cubiti.

30 Brachiseus internus.

3 1 Triceps extenfor cubiti.
12 Supinator radii longus.

J 3 Extenfores carpi radiales.

14 Extenfor communis digitorum.

1 5 Extenfor carpi ulnaris.

16 Flexor carpi ulnaris.

1 7 Anconeus.

18 Extenfor pollicis primus.

19 Extenfor pollicis fecundus.

C "6 )

TAB. XV.

1 Mufculus deltoides.

2 Pe&oralis.

3 Biceps flexor cubiti.

4 Triceps extenfor cubiti.

5 The fafcia tendinofa of the biceps mufcle*

6 Supinator radii longus.

7 Flexor carpi radialis.

8 Glutaeus.

9 Vaftus externus.

10 Biceps femoris.

1 1 Semitendinofus.

12 Semimembranofus.

13 Gaftrocnemius.

14 Solaeus*

4, B.

TAB. XV.

T.izf.

( i»7 )

TAB. XVL

1 Mufcu'lus rectus femoris.

2 Vaftus externus.

3 Vaftus internus.

4 Sartorius.

5 PecHnaeus.

6 The large head of the triceps,

7 Gaftrocnemius.

8 Solseus.

9 Membranofus.
io Rectus femoris.

1 1 Vaftus internus.

1 2 Vaftus externus.

13 Sartorius.

14 Pectinseus.

15 Gaftrocnemius.

16 Solaeus.

17 Tibialis anticus.

18 Extenfores digitorum.

TAB,

( "8 )

TAB. XVII.

1 Mufculus abdu&or pollicis.

2 Addu&or pollicis.

3 Flexor brevis.

4 Quadratus feu palmaris brevis.

5 The ftrong ligament of the carpus that bind9
down the tendons of the flexors of the fingers.

6 Abdu&or minimi digiti.

7 A probe under the tendons of the perforatus.
S A probe under the tendons of the perforans,
9 Lumbricales.

io Perforatus.

1 1 Flexor carpi radialis.

12 Flexor carpi ulnaris.

TAB.

TAB.XVTL.

V

TAH.XVm

»v

"W

( I2 9 )

TAB. XVIII.

i Tendo achilles.

2 That part of the aftragalus which articulates

with the tibia.

3 The tendon of the tibialis anticus.

4 The tendon of the extenfor pollicis pedis longus.

5 The tendons of the extenfor digitorum com-

munis.

6 Extenfor pollicis pedis brevis.

7 Extenfor digitorum brevis.

8 The union of the tendons of the extenfor Iongus

and the extenfor brevis,

TAB.

( *3° )

TAB. XIX.

i Mufculus triceps extenfor cubiti.

2 Deltoides.

3 Teres major.

4 Latiffimus dorfi.
^ Pe&oralis.

6 Obliquus defcendens abdominis*

7 Redus abdominis.

8 Sartorius.

9 Rectus femoris.
i o Vaftus externus.

1 1 Vaftus internus;

12 Gaflrocnemius.

13 Solaeus.

j 4 Tibialis anticus.

T A &

J>/30

TAB. XX.

( *3* )

TAB. XX.

This table is done after the famous ftatue of
Hercules and Antaeus. The mufcles here exhib-
ited being all explained in the other plates, the
figures are omitted to preferve the beauty of the
plate.

THE

THE

ANATOMY

OF THE

HUMAN BODY.

BOOK III.

CHAP.

Of the External Parts, and Common

Integuments.

A HE vulgar names of the external parts
of the human body being fufficiently known
for the defcription of any difeafe or operation j I
ihall only defcribe thofe which anatomifts have
given for the better undeiilanding of the fub-con-
tained parts.

• The hollow on the middle of the thorax, under
the breafts, is called fcrobiculus cordis ; the middle
of the abdomen for about three ringers breadth

above

134 EXTERNAL PARTS, <kc.

above and below the navel, is called regio um-
bilicalis; the middle part above this, cpigak
trium ; on each fide of the epigaftrium, under the
cartilages of the lower ribs, hypochondrium ; and
from below the regio umbilicalis, down to the offa
ilia and offa pubis, hypogaftrium..
• Cuticula, or fcarf-fkin, is that thin infenfible
membrane which is raifed by blifters in living
bodies. It is extended over every part of the true
fkin, unlefs where the nails are. » It appears to me
in a microfcope a very fine fmooth membrane, only
unequal where the reticulum mucofum adheres
to it. Lewenhoeck, and others, fay it appears
fcaly, and compute that a grain of fand of the
hundredth part of an inch diameter, will cover
two hundred and fifty of thefe fcales, and that each
fcale has about five hundred pores ; fo that a grain
of fand will cover 1 25,000 pores through which
we perfpire. • Its ufe is to defend the true fkin that
it may not be expofed to pain from whatever it
touches ; and alfo to preferve it from wearing;
it is thickeft on thofe parts of the bottom of the
foot which fuftain the body, and in hands much
ufed to labour, being 10 contrived as to grow the
thicker the more thofe parts are ufed. In fcorbu-
tic difcrders the cuticula will fometimes become
fcurfy and full of little ulcers, which are apt to
remain even when the caufe is taken away, but the
cuticle being taken off by a blifter, the new cuti-
cle will be found ; and though the cutis is alfected

and

EXTERNAL PARTS, Sec. 135

and full of little tumors, the difcharge of the blif-
ter will often cure them alfo.
• Between this and the true fkin is a fmall
quantity of flimy matter,, which was fuppofed by
Malpighi and others, to be contained in proper
vefTels, interwoven ^with one another, and there-
fore by them named reticulum mucofum.. It is
moft considerable where the cuticula is thickeft,
and is black, white, or dufky, fuch as is the com-
plexion ; the colour of this and the cuticula being
the only difference between Europeans and Afri-
cans or Indians, the fibres of the true fkin being
white in all men ; but the florid colour of the
cheeks is owing to the blood in the minute veffels
of the fkin, as that in the lips to the veffels in the
mufcular flefh ; for the cuticula being made of
excrementitious matter, has no blood veffels.
• Cutis, or true fkin, is a very compact, ftrong,
and fenfible membrane, extended over all the
other parts of the body, having nerves terminat-
ing fo plentifully in all its fuperficies, for the
fenfe of touching, that the fineft pointed inftru-
ment can prick no where without touching fome
of them.. Thefe nerves are faid by Malpighi
and others, who have examined theiacarefiilly, to
terminate in fmall pyramidal papilla ; iWerthelefs,
it feems that a plain fuperficies of the fkin is much
fitter and more agreeable to what we experience of
this fenfation ; for a plain fuperficies expofmg all
the nerves alike, I think, would give a more equal

fenfation,

136 EXTERNAL PARTS, &c.

fenfation, while nerves ending in a pyramidal pa-
pilla would be exceeding fenfible at the vertex of;
that papilla ; and thofe at the fides and round the
bafe, which would be far the greateft part, would
be the leaft ufeful. Immediately under the fkin
upon the fhin bone, I have twice feen little tumors
lefs than a pea, round and exceeding hard, and fo
painful that both cafes were judged to be cancerous;
they were cured by extirpating the tumor : but
what was more extraordinary, was a tumor of this
kind, under the fkin of the. buttock, frnall as a
pin's head, yet fo painful that the leaft touch
was infupportable, and the fkin for half an inch
round was emaciated ; this too I extirpated, with
fo much of the fkin as was emaciated, and fome
fat. The patient, who before the operation could
not endure to fet his leg to the ground, nor turn
in his bed without exquifite pain, grew immedi-
ately eafy, walked to his bed without any com-
plaint, and was foon cured.

' Glandulse miliares are fmall bodies like mil-
let feeds, feated immediately under the fkin in the
axillas ; and are faid to have been found under all
other parts of the fkin, where they have been
looked for with microicopes. » Thefe glands are
fuppofed to feparate fweat ; which fluid was thought
to be only the materia perfpirabilis flowing in a
greater quantity, and condenfed, till Sanctoti ius
aifured us that it is not fo, and that more of the
materia perfpirabilis is feparated in equal times than

of

EXTERNAL PARTS, &c. 137

of fweat ; of the former, he fays/ufually fifty-two
ounces a day in Italy, where his experiments were
made, and of the latter not near To much in the
mod profufe fwcats ; which feems to favour the
opinion of the exiftence of thefe glands : but who-
ever reads Mr. Hales's experiments will find,
that what Sanctoriu's accounted for by an
imaginary infenfible perfpiration, different from
thaf which in the greatefV degree produces fweat,
is really made by the lungs in refpiration, and is
ten times more than all the ordinary perfpiration
through the cutis, and feems to be but the fame
kind of fluid difcharged both ways ; for whenever -
it is interrupted through the {kin in cold weather,
then the lungs are overcharged, which occafions
coughing to get rid of it, which in a greater
degree is an afthma. Hence too it is, that thofe
who perfpire molt in the fummer are moft fub-
jecl: to afthmatic drforders in the winter ; and moft
of all fo, when the air they breathe is fulleft of
vapour, and therefore lead capable of conveying
this "matter from the lungs. That this kind of
perfpiration is very great, is fufficiently fhewn by
breathing upon glafs, or any thing that is fmooth
and cold.

• Membrana adip<5fii is all that membrane imme-
diately under the fkin, which contains. the fat
in cells'; -it is thickeft on the abdomen and but-
tocks, and thinneft neareft the extremities ; and
where the mufcles adhere to the fkin^ and on the

• penis,

K

i 3 8 EXTERNAL PARTS, &c.

penis, little or none.. It contributes to keep the in-
ner parts warm, and by filling the interfaces of
the mufcles, renders the furface of the body fmooth
and beautiful, and may ferve to lubricate their fur-
faces. Whether the decreaie of fat, which often
follows labour or ficknefs, proceeds from its being
re-afiumed into the blood veffels, or whether it is
conflantly perfpiring through the fkin, and the
leffening of its quantity is from the want of a fup-
ply equal to its confumption, is with me a matter
of doubt, though the former opinion, I know, gen-
erally prevails. The cells of this membrane com-
municate throughout the whole body fo much,
that from any one part the whole may be filled
with air. I have feen two cafes where the wind-
pipe being cut, and the external wounds being
clofely ftitched by injudicious furgeons, the air
that efcaped at the wound of the wind-pipe get-
ting into the cells of the membrana adipola, blew
up the upper part of the body like a bladder.
The like accident I have feen from a broken rib,
where, I fuppofe, the end of the rib had pricked
the lungs ; all thefe perfons died. In thefe cells
the water is contained in an anafarca, which from
its weight, firft fills the depending parts, as the
air in the former cafes did the upper parts ; and
when thefe cells are very full, the water frequently
pafTes from them into the abdomen, and after
tapping, though the limbs were ever fo full,
they will almoft empty themfelves in one night's

time.

EXTERNAL PARTS, &c. 139

time. This membrane is the ufual feat of im-
poftumations and boils, in both which nature,
uninterrupted, always corrodes a hole in the fkin ;
from whence we may learn, that the beft way of
opening any impoftumation is by a hole, and that
too as near the time of its breaking naturally as
may be, that nature may make the utmpft ad-
vantage of the difcharge. There is fomtiime.3 a
large kind of boil or carbuncle in this membrane,
which firft makes a large flough and a number of
fmall holes through the fkin, which in time mor-
tifies and cafts off, but the longer the flough is
fuffered to remain, the more it difcharges, and the
more advantage to the patient ; at the latter end of
which cafe the matter has a bloody tincture, and a
bilious fmell, exa&ly like what comes from ulcers
in the liver ; and both thefe cafes are attended with
fweet urine, as in a diabetes.
- Mammae, the breafts, feem to be of the fame
ftru&ure in both fexes, but largeft in women.
Each breaft is a conglomerate gland to feparate
milk, with its excretory ducts ; which are capable
of very great diftention, tending toward the nipple,
which as they approach, they unite, and make but
a few duds at their exit. ; There are to be met
with in authors inftances attefted of men giving
fuck, when they have been excited by a vehement
defire of doing it : and it is a common obfervation,
that milk will flow out of the breafts of new-born
children, both male and female.

K 1 Thc

140 EXTERNAL PARTS, &c

The breafts and uterus in women, the tongue,
mouth, and penis in men, and tlj|p eyes in chil-
dren, are the parts mod fubjedt to cancers ; yet
there is no part where this difeafe has not fome-
times fixed. It is a matter of difpute among fomc
furgeons, whether cancerous tumors mould ever be
extirpated or not, though it is certain none of thefe
ever were cured without, and being extirpated,
there have been many. The objection againft ex-
tirpation is this, that the operation often provokes
the part, which otherwife might lie quiet : but I
do not think this is true ; in defperate cafes, where
we cannot extirpate, we find the beft remedy is
plentiful bleeding, (which alfo is nature's laft refort)
gentle conftant evacuations by ftool, and a vegeta-
ble diet ; and though phyfic never cures while the
tumour remains, yet after extirpation it is highly
ufeful, and even the worft conftitutions have fome-
times been brought to their primitive Hate. An
eminent furgeon in the city, having a patient with
a cancerated breaft, extremely large, and fo much
ulcerated that the flench of it was infupportable ;
fhe infifted upon the extirpation, againft all advice,
with no other hopes but to be delivered from the
offenfive fmell. Some time after the operation, the
wound looking extremely fordid, he fprinkled it
.all over with red mercury precipitate, which put
the patient into a high falivation, upon which the
breaft grew clean and healed, the patient recover-
ed, and, contrary to all expectation, lived many

years

MEMBRANES in general. 141

years in good health. From this accident I learnt
the ufefulnefs of falivating, after extirpating can-
cerous tumours, though nothing is more hurtful be-
fore. In the extirpation of a breaft, and all other
tumours, as much ikin asis pomble mould be faved;
for the lofs of a great deal of ikin is fufficient to
make an incurable ulcer in the moil healthful body,
and much more fo in a bad conflitution.

CHAP. II.
Of the Membranes in general.

EVERY diftincl: part of the body is covered,
and every cavity is lined with a fingle mem-
brane, whofe thicknefs and ftrength is as the bulk of
the part it belongs to, and as the friction to which
it is naturally expofed.

Thofe membranes that contain diftinct parts,
keep the parts they contain together, and render
their furfaces fmooth, and lefs fubjecl: to be lace-
rated by the adtions of the body ; and thofe which
line cavities ferve to render the cavities fmooth, and
fit for the parts they contain to move againft.

The membranes of all the cavities that contain
folid parts, are ftudded with glands, or are provided
with vefTels, which feparate a mucus, to make the
parts contained move glibly againft one another,
and not grow together j and thofe cavities which
are expofed to the air, as the nofe, ears, mouth,

and

*4a SALIVARY GLANDS.

and trachea arteria, have their membranes befet
with glands which feparate matter to defend them
from the outer air. Thofe membranes that have
proper names, and deferve a particular defcription,
will be treated of in their proper places.

CHAR III.
Of the Salivary Glands.

iAROTIS, or maxillaris fuperior, is the larg-
er of the falivary glands ; it is fituate behind

lower jaw, under the ear ; its excretory dud:
paiTes ever the upper part of the mafleter muf-
cle, and enters the mouth through the bucci-
nator. . This gland has its faliva promoted by the
motions of the lower jaw. Its duct pafles over the
tend'neus part of the mafTcter mufcle, that it may

be compreffed by that mufcle, which would
cbftruct the faliva in it, though it is frequently faid
that it panes over that mufcle that it may be com-
preffed by it, to promote the faliva. In fheep,
hories, &c. whofe jaws are long, this mufcle is in-
ferted far from the centre of motion, that the end
of the jaw may be moved with fufficient ftrength,
and that diftant infertion requiring a greater length
of mufcle, that its motion may be quick enough,
no part of this mufcle could be allowed to be ten-
dinous ; therefore, it feems, to avoid the inconve-
nience

SALIVARY GLANDS. 143

nienec of compreffion from the mufclc, the duel: in
thofc animals goes quite round the lower end of it.
When this duel: is divided by an external wound,
the faliva will flow out on the cheek, unlefs a con-
venient perforation be made into the mouth, and
then the external wound may be healed. I have
feen patients with this gland ulcerated, from which
there was a conftant effufion of faliva, till the
greateft part of the gland was confirmed with red
mercury precipitate ; and thenthey healed with little
trouble. Hi l d a n u s mentions the fame cafe, which
for two years had been under the care of a furgeon
without fuccefs ; and was at laft cured by the ap-
plication of an actual cautery.

• Maxillaris inferior is fituate between the low-
er jaw and the tendon of the digaftric mufcle..
Its duel paffes under the mufculus mylohyoideus,
and enters the mouth under the tongue, near the
dentes inciforii. I was at the opening of a woman
who was fuffocated by a tumor which begun in this
gland, and extended itfelf from the fternum to the
parotid gland on one fide in fix weeks time, and in
nine weeks killed her ; it was a true fcirrhus, and
weighed twenty-fix ounces. In a man which I
differed, I found a quantity of pus near this gland,
and a bundle of matter not unlike hair, as large as
an hen's egg.

» Sublingualis is a fmall gland fituated under the
tongue, between the jaw and the ceratoglofTus
mufcle. . In a calf I found feveral duds of this

gland

144 SALIVARY GLANDS.

gland filled by an injection into the duel: of the
fubmaxillary gland; but Morgagni and others
fhew, that the duds of this gland enter the mouth
directly from the gland in feveral places near the
grinding teeth.

* Toniilla is a globular gland, about the bignefs
of a hazel nut, lituate upon the pterygoideus in-
ternus mufcle, between the root of the tongue and
the uvula.* It has no duel continued from it, but
empties all its fmall duels into a firms of its own,
which linus, when the gland is inflamed, may ea-
fily be miftaken for an ulcer. This gland with its
fellow direct the mafticated aliment into the pha-
rynx, and alfo ferve for the uvula to (hut down
upon when we breathe through the nofe. They are
compreffed by the tongue and the aliment, when
the former raifes the latter over its root, and there-
by opportunely emit their faliva to lubricate the
food for its eafier defcent through the pharynx. A
fcirrhous tumor of either of thefe glands is a com-
mon difeafe, and it admits of no remedy but ex-
tirpation. The beft way of extirpating them, is,
I think, by ligature : if the gland is fmall at its
bafis, the ligature may be tied round it, which I
have often performed by fixing the ligature to the
end of a probe bent, and fo drew it round the
gland, and tied it ; and in a few days the glands
d "Topped of: but meeting with other cafes of this
kind, where the bafis of the gland was too large to
tie, I contrived an inftrument like a crocked needle

fet

SALIVARY GLANDS. 145

fet in a handle, with an eye near the point ; I thruft
this instrument, with a ligature into it through the
bottom of the gland, and then taking hold of the
ligature with a hook, I drew back the inftrument ;
then drawing the double ligature forwards, I divid- •
ed it, and tied one part above and the other below,
in the fame manner that I did to extirpate part of
the omentum in the cure of an hernia, and this
fucceeded as well as the former. See the plate at
the latter end of this book.

Preffure upon the furface of a gland very
much promoting the fecretion that is made in it,
thefe glands are fo feated as to be prefled by the
lower jaw, and its mufcles, which will be chiefly
at the time when the fluid is wanted ; and the
force with which the jaw muft be moved, being
as the drynefs and hardnefs of the food mafticated,
the fecretion from the glands depending very much
upon that force ; it will alfo be in proportion to the
drynefs and hardnefs of that food which is neceffa-
ry ; for all food, being to be reduced to a pulp,
by being broke and mixed with faliva, before it
can be fwallowed fit for digeftion, the drier and
harder foods needing more of this matter, will from
this mechanifm be fupplied with more than moift-
er foods in about that proportion in which they
are drier and harder ; and the drier foods needing
more faliva than moiiter, is the reafon why we
can eat lefs, and digeft lefs of thefe than thofe.
What quantity of faliva thefe glands can feparate

from

i+6 SALIVARY GLANDS.

from the blood, in a given time, will be hard to de-
termine, but in eating of dry bread it cannot be lefs
than the weight of the bread ; and many men,
in a little time, can eat more dry bread than twice
the fize cf all thefe glands ; and fome, that are not
ufed to fmoaking, can fpit half a pint in the fmoak-
ing one pipe of tobacco ; and fome men in a fali-
vation, have fpit, for days or weeks together, a
gallon in four and twenty hours ; and yet, I be-
lieve, all thefe. glands put together, do not weigh
more than four ounces.

* The membrane which lines the mouth and pal-
ate, and covers the tongue, is every where befet
with fmail glands, to afford faliva in all parts of
the mouth to keep it moift ; for thofe more remote
are chiefly concerned in time of maftication., Thefe
fmali glands have names given them according to
their refpec~live fituations, as buccales, labiales,
linguales, fauciales, palatinse, gingivarum, and

uvulares.

A gland is chiefly compofed of a convolution
of one or more arteries of a confiderable length,
from whofe fides arife a vail number of excretory
dudts, as the lad:eals arife from the guts, to receive
in each giand their proper juices, as the lactcals do
the chyle; and though the larger fecretions are made
by vifible glands, yet unconvolved arteries may alfo
have excretory duds for the fame purpofe. And
this way, I imagine, fecretions are made from all
the membranes that line cavities, and fome others.

There

SALIVARY GLANDS. 147

There alfo arife from thefe arteries lymphatic vef-
feis, whofe ufe feems to be to take off the thinned
part of the blood, where a thick fluid is to be fe-
creted, feeing they are found in greateft plenty in
ftfcfe glands as feparate the thickeft fluids, as in
the te Hides and liver ; and it is obfervable that,
•where the thickeft fecretions are made, the velocity
of the blood is the leaft, as if it was contrived to
give thofe feemingly more tenacious parts more
time to feparate from the blood. The arteries that
compofe different glands are convolved in different
manners ; but whether or no their different fecre-
tions depend at all upon that, I doubt will be dif-
ficult to difcover. The excretory du£ts arife from
the arteries, and unite in their progrefs, as the roots
of trees do from the earth ; and as different trees,
plants, fruits, and even different minerals, in their
growing, often derive their diftincl:, proper, nu-
tritious juices from the fame kind of earth ; io the
excretory duels, in different glands, feparate from
the fame mafs of blood their different juices : but
what thefe different fecretions depend upon, wheth-
er the ftru&ure of the parts, or different attrac-
tions, or what elfe, we have no certainty about,
though this fubjecl: has employed feveral ingenious
writers. For my own part, from the great fimplic-
ity and uniformity ufually feen in nature's works,
I am moft inclined to think different fecretions
arife from different attractions, feeing that in plants
and minerals there feems to be no other way.

CHAP.

148 PERITONEUM,

CHAP. IV.

Of the Peritonaeum, Omentum, Ductus
Alimentalis, and Mesentery.

PERITONEUM is a membrane which lines
the whole cavity of the abdomen. It contains
the liver, fpleen, omentum, ftomach, guts, and
mefentery, with all their veffds and glands ; ithe
upper part of it is no other than the proper mem-
brane of the diaphragm, for there is no more rea-
fon to call that, part of the peritonaeum, than there
is for calling the membrane on the other fide of
the diaphragm, part of the pleura or mediaftinum.
The fore part next the mufcles of the abdomen,
and their tendons, may be divided into two lami-
nae, yet, I think, anatomifts in defcribing the du-
plicative or laminse of the peritonaeum have not
always meant this divifion, but have taken the ten-
dons of the tranfverfe mufcles for the outer lamina,
and confidered the other as one membrane, feeing
that it is between thefe tendons and the peritoneum
that the water is found in that kind of dropfy which
is called the dropfy in the duplicature of the peri-
tonaeum. Upon the Ibins the inner furface only is
fmooth, and the outer part a fort of loofc membra-
na adipofa, in which are contained the aorta, ve-
na cava, vafa fpcrmatica, and pancreas, with oth-
er parts of lefs note. The middle of the perito-
naeum upon the loins is joined to the mefentery

in

O M E N T U M, &c. 149

In fuch a manner, as makes fome account it. a pro-
duction of the peritonaeum, and fome part of the
external membrane of the duodenum, becoming
one membrane with the inner or fmooth lamina of
the peritonaeum, and part of the rectum is covered
in the fame manner ; but the kidneys and bladder
of urine are contained in a diftincT: duplicature of
this membrane. The dropfy of the peritonaeum
may be diftinguifhed by being leaft prominent
about the navel, for there the tendons and the
peritonaeum will not feparate ; and the water in
thofe that I have differed, had made the parts
where it was contained as foul as any ulcer ;
therefore none of them, I prefume, could have
been cured by operation.

For the umbilical veffels, fee chap. Of the foe-
tus. For the procefTus vaginalis, chap. Of the
parts of generation in men.

- Omentum, or cawl, is a fine membrane, larded
with fat, fomewhat like net-work. It is fitu-
ated on the furface of the fmall guts, and refem-
bles an apron tucked up ; -its outer or upper part,
named ala fuperior, is connected to the bottom
of the flomach, the fpleen, and part of the in-
teftinum duodenum ; and thence defcending a lit-
tle lower than the navel, is reflected and tied to
the inteftinum colon, the fpleen, and part of the duo-
denum ; this laft part is called ala inferior ; and the
fpace between the alse is named burfa. This cavi-
ty is very diftinct in moft brutes, but feldom fo in

men.

t S o DUCTUS ALIMENTALIS.

men. Sometimes both alas are tied to the liver,
and, in difeafed bodies, to the peritonaeum. Its life
is to lubricate the guts, that they may the better
perform their periflaltic motion. Malpighi de-
fcribes adipofe duels in this membrane to carry the
fat from the cells into the vena portos, and thinks
it a neceflary ingredient in the bile. In dropfies of
the abdomen, and in perfons who from any other
caufe have died tabid, it is generally 'rotten and de-
cayed ; and fometimes the guts in thefe cafes adhere
to one another : but whether thefe adhefions pro-
ceed from the omentum's ceafing to perform its
office, or from the periftaltic motion of the guts-
being long difcontinued through abftinence,or both,
I cannot determine.

♦ Ductus alimentalis, is the cefophagus, ftom-
ach, and guts, viz. duodenum, jejunum, ile-

v um, colon, csecum or appendicula vermifonnis, and
rectum. .

* CEibphagus, or gullet, is the beginning of the
alimentary duel: ; its upper part is wide and open,
fpread behind the tongue to receive the mafticated
aliment ; -"it begins from the bafis of the fcull, near
the proceffus pterygoides of the fphenoidal bone,
then defcending becomes round, and is called va-
ginalis gulae ; it runs from the tongue clofe to the
fpine,underthe left fubclavian blood veffels, into and
through the thorax on the left fide, then piercing
the diaphragm, it immediately enters the ftomach.
It is compofed of a thin outer coat, which is no

more

DUCTUS ALIMENTALIS. 151

rnore than a proper membrane to the middle or
mufcular coat. The middle coat is compofed of
longitudinal and circular mufcular fibres, but chiefly
circular, abundantly thicker than the fame coat
in the guts ; becaufe this has no foreign power to
affift it, as the guts have, and becaufe it is neccf-
fary the food mould make a fhorter ftay here than
there. The inner coat is a pretty finootii mem-
brane, befet with many glands, which fecrete a
mucilaginous matter, to defend this membrane,
and render the defcent of the aliment eafy.

• Ventriculus, the ftomach, is fituated under the
left, fide of the diaphragm, its left fide touch-
ing the fpleen, and its right is covered by the thin
edge of the liver ; its figure nearly refembles the
pouch of a bag-pipe, its left end being moft capa-
cious, the upper fide concave, and the lower con-
vex : it has two orifices, both on its upper part ;
the left, through which the aliment paffes into the
ftomach, is named cardia ; and the right, through
which it is conveyed out of the ftomach into the
duodenum, is named pylorus ; * where there is a
circular valve which hinders a return of aliment
out of the gut, but does not at all times hinder the
gall from flowing into the ftomach.

► The coats of the ftomach are three ; the exter-
nal membranous, the middle mufcular, whole fi-
bres are chiefly longitudinal and circular, the in-
ner membranous, and befet with glands, which
feparate a mucus. . This laft coat is again divided

by

i 5 2 DUCTUS ALIMENTALIS.

by anatomifts into a fourth, which they call villofa.
As the mufcular coat of the ftomach contracts, the
inner coat falls into folds, which increafc as the fto-
mach leiTens, and confequently retard the aliment
moft when the ftomach is neareft being empty.

The manner in which digeftion is performed
has been matter of great controverfy. The ancients
generally fuppofed the food concocted by a fermen-
tation in the ftomach : but the moderns more gen-
erally attribute it to the mufcular force of the fto-
mach ; which Dr. Pitcairne has computed to
be equal to a hundred and feventeen thoufand and
eighty-eight pounds weight ; to which being added
the abfolute force of the diaphragm and abdominal
mufcles (but for what reafon I am at a lofs to con-
ceive, when fo fmall a part of that force can be ex-
erted this way) the fum then will be more than'
twice as much ; a force indeed equal to the end for
which he afiigns it. Now this force of the mufcu-
lar coat of the ftomach is near forty times greater
than what Bor.elli has afligned to the heart,
which is much Pcronger ; and Dr. Keil has under-
taken to prove, that the force which the heart exerts
is not thrice as many ounces as Bohelli computes
it to be thoufand pounds weight. Yet this is as
certain, as that action and reaction are the fame ;
that the abdominal mufcles and the diaphragm
comprefs the ftomach with no greater force than
they clo the liver and all other parts contained in the
abdomen ; and that the fcetus in utero, and all the'

vifcera

DUCTUS ALIMENTALIS. 153

vifcera in the abdomen, receive much more of this
force, during the time of geftation ; and yet nei-
ther the foetus, nor any other contained part, is di-
gefted by that force ; and for the force with which
the flomach itfelf acts, it will be juft the fame with
the reaction of the food upon it, and therefore
mould be as much more liable to be digefied by
this and the other force, than the food, as it oftener
feels thefe forces than that (only that living bodies
are not fo liable to digeftion as dead ones :) befides,
it may be demonftrated, that the force with which
the ftomach compreffes any part of its contents, is
not greater than what is given to equal parts of the
contents in the fmall guts ; for if the moment of a
mufcle is as its weight, and if the mufcular coat of
the ftomach does not bear a greater proportion to
the mufcular coat of a fmall gut, than their diame-
ters bear ; a fection of the ftomach having fo many
more equal parts to prefs than a like fection of a
gut, it will require juft fo much more force to give
each part the fame preffure. Dr. Drake has fup-
pofed, that digeftion is performed in the ftomach,
as in Papin's Digefter ; in which hypothecs are
contained all the abfurdities of that of Pitc airne,
with this addition, that the ftomach muft be as ir-
refiftible to diftention at that time, as his iron pot,
and the orifices as forcibly fecured ; but then in-
deed it {hews how bits of bones, which dogs fwal-
low, may be retained in the ftomach without tear-
ing it; which difficulty, in my opinion, Dr. Pit-

L CAIRNE

i 5 4 DUCTUS ALIMENTALIS.

cairne has not fufficiently accounted for, though
it is none of the leaft in his hypotheiis. In gra-
nivorous birds, where digeftion is made by muicu-
lar force, their fecond ftomach is plainly contrived
for comminuting or digefting their food that way ;
for befides that it is one of the ftrongeft mufcles in
their bodies, its iniide is defended with a hard and
ftrong membrane that it may not be torn ; and
thefe birds always eat with their grain the rougheft
and hardeft little ftones they can find, which are
neceffary for grinding their food, notwithftanding
it is firft foaked in another ftomach, and is alfo
food of very eafy digeftion. In ferpents, fome birds,
and feverai kinds of fifh, which fwallow whole
animals, and retain them long in their ftomachs,
digeftion feems to be performed by a menftruum ;
for we frequently find in their ftomachs animals fo
totally digefted, before their form is deftroyed, that
their very bones are made foft. In horfes and oxen,
digeftion is but little more than extracting a tinc-
ture ; for in their excrements, when voided, we*fee
the texture of their food is not totally deftroyed,
though grafs, in particular, feems to be as ealily di-
vided as any food whatever, and the corn they eat is
often voided entire : and in the excrements of men,
are often feen the fkins of fruits undigefted, and
imall fruits fuch as currants, unbroke, and worms
alfo continue unhurt, both in the ftomach and guts.
Therefore, by comparing our ftomachs with thofe
here mentioned, it appears to me, that our digeftion

is

DUCTUS ALIMENTALIS. 155

is performed by a menftruum, which is chiefly
faliva, gently aflifted by the a&ion of the ftomach,
and the abdominal mufcles, and by that principle
of corruption which is in all dead bodies. For di-
geftion is no other than corruption or putrefa&ion
of our food ; therefore meats preferved from cor-
ruption by fait or fpirits, are hard of digeftion and
unwholefome. Neverthelefs, when this digefting
menftruum of the ftomach is too crude, the fame
falts or fpirits, moderately ufed, become a remedy ;
and though meat long faited is fo very unwhole-
fome, it feems not to be from the fait itfelf, but
the meat made undigeftible by being long faited ;
for thofe who eat the greatefl quantity of fait at
their meals are not fubjected thereby to the fame
diftempers. And this digefting menftruum, when
the ftomach is empty, exciting that uneafinefs
which we call hunger, our appetites and our di-
geftion are thereby necefiarily fuited both as to
time and quantity.

* Duodenum is the firft of the three fmall guts ;
it begins from the pylorus of the ftomach, and is
thence reflected downward ; it firft pafTes by the
gall-bladder, and then under the following gut and
mefentery, and coming in fight again in the left
hypochondrium, it there commences jejunum,
which is the fecond of the fmall guts ; but the
place where this ends and the other begins is not
precifely determined.;

L 2 Jejunum

156 DUCTUS ALIMENTALiS.

'led from its being found, for
moft part, empty ; it is fittrated in the regio
makes foifiewl >re than a

third p 11 guts. It is diftinguifhed

frc:: the following gut by its which are a

fmall matter thinner and lefs pale.j
' Ileum is the continuation of the former, fitua-
ted in the hypogaftrium, and very often fome
part of it in the pelvis of the abdomen, upon the
bladder of urine, efpecially in women ; it enters
the colon on the right fide, near the upper edge
of the os ilium.. This great length of the fmall
guts is evidently for the convenience of a greater
number of ladteals, that the chvle which milTes
their orifices in one place may not efcape them in
another ; but thofe animals which fwallow their
food whole, and have it a long time in their ftom-
ach and guts, have fhorter guts and fewer lacteals.
Colon is the firft of the great guiis ; it begins at
the upper edge of the right os ilium ; thence
afcending paffes under fome part of the liver, and
the bottom of the ftomach, from the right hypo-
chondrium tc the left, and thence defcends to the
pelvis of the abdomen.*

- Csecum, or appendicula vermiformis, is fitu-
ated on the beginning of the colon : it is lefs than
an earth-worm, with a fmall orifice opening in-
to the colon ; this gut has feldom any thing in
it.. In men it is called one of the large guts,
though it is the fmalleft by far j but the miftake

arifes

DUCTUS ALIMENTALIS. 157

arifes from copying the antients, whofe defcriptlons
of all the parts contained in the abdomen, feem to
be taken from dogs; for in them, and in many other
animals, it is very large : and fome fiih have them
in great numbers, but very fmall ; I have counted t
in a mackarel above one hundred and fifty.
" Rectum is the continuation of the colon through
the pelvis to the anus..* The lower end of this gut
is the feat of the true fiftula in ano, which ufually
runs betwixt the mufcular coat and the inner coat ;
it is cured by opening it the whole length into
the cavity of the gut ; it is yet better, if it can be
done, to extirpate all that is fiftulous and fchirrhous,
for that is a fure wa} to make one operation perfect
the cure. The other kind of fiftula, improperly fo
called, is an abfcefs running round the outfide of
the fphincter, in the fhape of a horfe-fhoe, being a
circle all but where this mufcle unites with thofe
of the penis ; this is befl cured by opening and re-
moving part of the outer fkin. The firft of thefe
cafes happens ofteneft in full habits, proceeding fre-
quently from the piles ; the laft is generally a criti-
cal difcharge, and one of nature's laft efforts in con-
fumptive and fcorbutic habits of body. The inver-
fion and fliding down of this gut is called prolapfus
ani, a difeafe common in children, efpecially thofe
who are afflicted with the ftone, and of not much
confequence ; in men it is more rare and more
dangerous, being generally attended with a flux of
humours. This cafe I have cured by taking away a

piece

158 DUCTUS ALIMENTALIS.

piece of the prolapfed gut with a cauftic, length-
ways of the gut ; the wound difcharged the flux of
humours, upon which the gut was eafily reduced,
and cicatrifmg in that ftate it never more fell down.

I have feen a cafe, where a bold unthinking
furgeon having cut off the prolapfed part, the ci-
catrix was fo hard and contracted that the patient
could never after go to ftool without a clyfter, and
then not without great mifery.

Oftentimes the piles occafion large tumours at
the lower end of this gut ; thefe are always
belt, extirpated by ligature ; for if they are cut,
they will fometimes bleed excefiively, and it is no
eafy matter to apply any thing to flop a flux of
blood in that part.

* The guts have the fame coats with the ftomach ;
the fibres of their middle or mufcular coat are cir-
cular, or fpiral, and longitudinal ; of the latter but
very few. . The antagonifts to thefe mufcular fibres
of the ftomach and guts, are their contents preffed
from one place to another, and the mufcles of the
abdomen, for thefe preffing upon them alter their
form into one lefs capacious ; which neceflarily
extends their circular fibres. The great guts have
three membranes, or ligaments, on the outfide, run-
ning their whole length, and fupporting the facculi,
into which thofe guts are divided. The letter guts
have, at very fmall diftances,femilunar valves placed
oppofite to the interftices of each other, to prevent
the aliment from pairing too fpeedily through the

guts ;

DUCTUS ALIMENTALIS. 159

guts ; and the better to anfwer that end, they are
larger and more numerous near the ftomach, where
the food is thinner, than they are towards the colon,
where the food is continually made thicker in its
progrefs, by a difcharge of part of the chyle. This
contrivance, fo neceffary to men, becauie of their
erect pofture, when they are obliged, by ficknefs
or accidents, to lie along, becomes a great inconve-
nience, and calls for the help of ciyfters and purges.
But brutes have not thefe valves, becauie they are
not convenient in an horizontal pofture. At the
entrance of the ileum into the colon, are two very
large valves, which effectually hinder the regrefs of
the fceces into the ileum. But ciyfters have been
frequently known to pafs them, and be vomited
up ; though the excrement that is fometimes vomited
up, I am inclined to think, is fuch as had not paus-
ed into the great guts. The other valves in the
colon are placed oppofite, but not in the fame
plane, to each other, and make, with their ante-
rior edges, an equilateral triangle ; but as the gut
approaches the anus, they become lefs remarkable,
and fewer in number.

AH the guts have in their inner membrane an
almoft infinite number of very fmall glands : thefe
glands will, efpecially fome of them in the large
guts, appear to the naked eye when they are dif-
eafed : they are called glandular pyerianae.

The length of the guts to that of the body is
as five to one in a middle-fized man ; in taller men

the

160 MESENTERY.

the proportion is ufually lefs, and in fhort men
greater.

• Mefentery is a membrane beginning loofely up-
on the loins, and is thence produced to all the guts :
it preferves the jejunum and ileum from twifting
in their periftaltic or vermicular motion, and con-
fines the reft to their places. ; It fuftains all the
veflels going to and from the guts, viz. arteries,
veins, lymphceducTis, lacleals and nerves, and alfo
contains many glands, called, from their fituation,
mefentericse. The beginning of this membrane
from the loins, is about three or four inches broad,
but next the guts of the fame length with the fide of
the guts they adhere to, which is in the fmall guts,
about a fourth part fhorter than the other fide ; but
when this membrane is feparated from the fmall
guts, it fhrinks, and meafures about two thirds lefs.
I opened a boy, about twelve years old, that di-
ed of the iliac paffion, vulgarly called the twifting
of the guts ; the guts, ftomach, duodenum, and
jejunum were diftended, with vapour and air, to
near ten times their natural capacity, which fo com-,
prefled the inteftinum ileum, that nothing could
pafs through it. The relations of this boy could
give no other account of the caufe of this difeafe,
than that of his having eaten a large quantity of
raw young carrots. This cafe happens very fre-
quently to lambs that have been houfed, and turned
out early in the fpring to grafs, when the grafs is
very rank and fucculent ; and alfo to horfes, oxen,

and

LIVER. 161

and fheep, when they happen to feed, by any ac-
cident, upon young beans or peas, or rich clover
grafs, which are very apt to ferment in their ftom-.
achs. In thefe animals this cafe is commonly cur-
ed by running a knife into their guts ; fome in-
ftances of which I have feen, and have heard a
great many reported ; but this cafe happening very
rarely to men, I believe that practice has never yet
been ufed j though the inftrument which is ufed
for tapping in a dropfy of the abdomen, might do
it with great eafe and fafety. Some anatomifts,
who have confidered the impoffibility of a twitting
of the guts, which is the vulgar name of this dif-
eafe, have imagined that it proceeded from one
gut being involved in another. Thefe involutions
are found frequently in bodies that die a natural
death, and without any inflammation, or any other
fymptom of pain.

CHAR V,

Of the Liver, Gall-Bladder, Pancreas
and Spleen.

1 HE liver is the .largeft gland in the body ; of a
dufky red colour. It is fituated immediately un-
der the diaphragm in the right hypochondrium ;
its exterior fide is convex, and interior concave ;
backward toward the ribs it is thick, and thin
on its fore-part, where it covers the upper fide

of

i6z LIVER.

of the ftomach, and fome of the guts ; the upper
fide of it adheres to the diaphragm, and is alfo tied
to it and the fternum by a thin ligament, which is
defcribed commonly as two ; the upper part called
fufpenforium, and the anterior latum : but either
of thefe names is fufficient for it all. , It is alfo tied
to the navel by a round ligament called teres or
umbilicale, which is the umbilical vein degenerated
into a ligament ; it is inferted into the liver at a
fmall fiflure in its lower edge. The ligamentum
latum, or fufpenforium, fuftains the liver in an ered
pofture, or rather fixes it in its fituation, while it
is fupportcd by the other vifcera, they being com-
preffed by the abdominal mufcles ; in lying down
the teres prevents it from preffing on the diaphragm ;
and in lying on the back, they both together fuf.
•pend it, that it may not comprefs and obftruct the
afcendir.g vena cava. It is nourifhed by the branches
of the celiac and mefenteric arteries in the liver,
called arterise hepaticse, but its blood veffels, that
compofe it as a gland, are the branches of the vena
portse, which enters the liver, and diftributes its
blood like an artery, to have the bile fecreted from
it ; and the branches of the cava in the liver, which
return the redundant blood into the cava afcendens :
it has alfo feveral branches of nerves, and a great
number of lymphatics ; of which I fhall treat in
their refpective places. Dogs and cats, and other
animals, that have a great deal of motion in their
backs^ have their livers divided into many diflincT:

lobules ;

GALL-BLADDER. 163

lobules ; which, by moving one againft another,
comply with thole motions, which elfe would break
their livers to pieces.

• The gall-bladder is a receptacle of bile, feated
in the hollow fide of the liver ; it is compofed of
one denfe coat -fomewhat mufcular, which is cov-
ered with a membrane like that of the liver ; and
is alfo lined with another, that cannot eafily be fep-
arated. . Modern anatomifts have defcribed a num-
ber of fmall duels leading from the liver to the gall-
bladder, by which they fuppofe the gall-bladder is
filled ; and thefe I thought I had {cen in a human
body that died of a jaundice, when I was a very
young anatomift ; but never being able to fee any
fince in any animal, though I have made very dili-
gent inquiry by experiments and diffection, I am
now perfuaded that there are no fuch ducts j for if
they are too little to be {ten. or filled by injections,
I think they are too little for the end for which
they are afligned. As to the argument for the ex-
iftence of fuch duels, which is fetched from the
difficulty of the gall-bladder's being filled through
the ductus cyfticus from the ductus hepaticus, I
think it is of little weight, feeing the veficulss femi-
nales are filled with a thicker fluid through a lefs di-
rect paffage. From the gall-bladder towards the du-
odenum runs a duct called cvfticus ; and from the
liver to this duct one called hepaticus, which car-
ries off the gall this way, when the gall-bladder
is full ; then the ductus cyfticus and hepaticus

being

164 GALL-BLADDER.

being united, commence ductus communis chole-
dochus, which enters the duodenum obliquely
about four inches below its beginning. The ori-
fice of this duel: in the gut is fomewhat eminent,
but has no caruncle, as is commonly faid. As
t<he liver, from its fituation in the fame cavity with
the ftomach, will be moft prefied, and confequent-
ly feparate moft gall when the ftomach is fulleft,
which is the time when it is moft wanted j fo the
gall-bladder, being feated againft the duodenum,
it will have its fluid prefled out by the aliment
pafiing through that gut, and confequently at a
right time and in due proportion ; becaufe the
greater that quantity of aliment is, the greater will
be the comprefiion ; and fo the contrary.

I know no way of computing, with any exacl:-
nefs, the quantity of bile that is ufually fecreted by
the liver in a given time ; but if it is four times as
much as all the falivary glands fecrete, it may be
twenty-four ounces for every meal : to which be-
ing added fix ounces of faliva, which, from what
is obferved in the chapter of the falivary glands, I
think will appear a moderate computation : and
fuppofmg the pancreas in the fame time fecretes
three ounces, there will then be thirty-three
ounces of fluids feparated for the digeftion of one
meal ; and that thefe neceflary fluids may not be
wafted in fuch quantities, they pafs into the blood
with the chyle, and may be foon feparated again for
the fame ufe ; and very likely, fome of the fame bile

may

PANCREAS. 16$

may be employed more than once, for digefting part
of the fame meal : and as the liver exceeds all the
glands in the body in magnitude, and its excreto-
ry duds ending in the duodenum, it feems to me
to be much more capable of making thofe large
feparations from the blood, which are procured by
cathartics, than the fcarce vifible glands of the guts.
The liver ordinarily weighs, in a middle-fized man,
about three pounds twelve ounces, the pancreas
three ounces, and the fpleen fourteen ounces. I
have feen a difeafed liver in a man that weighed
fourteen pounds four ounces : and in a boy but nine
years old, that died hydropic, the liver full of hy-
datids, and cyfts of hydatids adhering to it, which
together weighed feven pounds one ounce and a
half, though feveral pints of water had been let out
of it before. The fpleen in the fame boy, together
with the hydatids contained in its membrane,
weighed three pounds. In a man I found a difeafed
fpleen, weighing five pounds two ounces ; and in
an old man, fix foot high, I found a found liver
weighing no more than twenty-eight ounces, and
the fpleen but ten ounces : and in a man that had
been cured of a dropfy I found a polypus very folid,
almoft filling the large branches of the porta in the
liver, and a ftone between the liver and gall-blad-
der, larger than a nutmeg.

. Pancreas, the fweet-bread, is a large gland
of the falivary kind, lying acrofs the upper and
back part of the abdomen, near the duodenum ; it

has

166 PANCREAS.

has a fhort excretory duel:, about half as large as a
crow quill, though it is commonly painted as large
as the ductus communis choledocus :• it always en-
ters the duodenum together with the bile duel: ; but
in dogs fome diftance from it ; and, I think, al-
ways in two duels diftant from one another. The
juice of thjs gland, together with the bile, helps to
complete the digeftion of the aliment, and renders
it fit to enter the lacteal veflels. In a man that died
of a jaundice, I found the ductus communis chole-
dochus conftrictcd by a fcirrhous pancreas, the
gall-bladder extended to the fize of a goofe egg;,
and all the duels to twice their natural bignefs.
This is the cafe in which I thought I had fo plainly
feen the cyftihepatic duds : I once faw the ductus
cyfticus obltructed, without the gall-bladder be-
ing diftended, which, I think, furnifhes us with
a very probable argument againft the exiftence of
cyftihepatic ducts. In thofe who die of the jaun-
dice, for the moft part are found in the gall-bladder
and the biliary ducts concretions of bile fo light as
to fwim in water, yet are called gall-Hones : thefe
caufe the jaundice, by obftructing the ducts : many
of thofe who have been cured of this difeafe, have
had great numbers of thefe ftones found in their ex-
crements. A patient of mine, who had voided by
ftool feveral of thefe ftones, had afterwards two of
half an inch diameter, which made their way
through the integuments of the abdomen, anc 1 is
cured without much pain. Oxen, as the fam( n-

tleman

SPLEEN. 167

tieman informed me, who have been long fed upon
rymeat, abound with them ; while others, fed with
them, and afterwards turned to grafs, when killed,
are found without them. This gentleman could
never eat any herbs. He alfo informed me of a
phyfician in France, that with great reputation
cured the jaundice by giving his patients large
quantities of the juice of herbs.
• The fpleen is feated in the left hypochondrium,
immediately under the diaphragm, and above the
kidney, between the ftomach and the ribs ; it is
fupported by the fub-contained parts, and fixed to
its place by an adhefion to the peritonaeum and dia-
phragm ; it is alfo connected to the omentum, as
has been obferved. « The figure of it is a fort of de-
preffed oval, near twice as long as broad, and almcft
twice as broad as thick. Sometimes it is divided into
lobules, but for the moft part has only one or two
fmall fiflures on its edge, and fometimes none; in
its colour it refembles caft iron. The inner texture,
in brutes, is veficular, like the penis ; in which
veficles are found grumous blood, and fmall bodies
like glands: but Ruysch denies that the human
fpleen is of the fame texture. The fpleen I have
feen taken out of a dog, without any remarkable
inconvenience to him. I have twice, in a human
body, feen three fpleens, twice two,»and once four ;
fome of thefe were very fmall, others nearly equal,
but altogether in any of thefe bodies were not
larger than the one which is ufually found.

C H A P.

168 VASA LACTEA.

CHAR VI.

Of the Vasa Lactea.

. V ASA la&ea are the venae la&eae, receptaculum
chyljj and du&us thoracicus. .
. Venae la&eae, &c. are a vaft number of very-
fine pellucid tubes, beginning from the fmall guts,
and proceeding thence through the mefentery ;
they frequently unite, and form fewer and larger,
veffels, which firft. pafs through the mefenteric
glands, and then into the receptaculum chyli.,Thcfe
veffels, ere they arrive at the mefenteric glands, or
in dogs the pancreas afellii, which is thefs glands
collected, are called venae la&eae primi generis ; and
thence tq their entrance into the receptaculum chy-
li, venae lacteae fecundi generis. The office of thefe
veins is to receive the fluid part of the digefted ali-
ment, which is called chyle, and convey it to the
receptaculum chyli, that it may be thence carried
through the ductus thoracicus into the blood veffels.
For the following excellent defcription, thus
marked " , of the receptaculum chyli, and ductus
thoracicus, I am obliged to Mr. Monro.
• " Receptaculum chyli pecqueti, or faccus lac-
" teus van home, is a membranous fomewhat
" pyriform bug, two thirds of an inch long,
" one third of an inch over in its largeft part,
u when collapfed ; fituated on the firft vertebra
" lumbrorum, to the right of the aorta, a little higher

" than

VASA LACTEA* i6g

u than the arteria emulgens dextra, under the right
** inferior mufcle of the diaphragm. . It is formed
" by the union of three tubes ; one from under
u the aorta, the fecond from the interflice of the
" aorta and cava, the third from under the emulgents
" of the right fide. The facchus chyliferus at its
" fuperior part becoming gradually fmaller, is con-
" tracked into a flender membranous pipe of about
*? a line diameter, well known by the name of
• " Du&us thoracicus. This partes betwixt the
"appendices mufculofse diaphragmatis, on the
" right of, and fomewhat behind the aorta, then
" lodged in the cellular fubftance under the pleu-
** ra ; it mounts between this artery and vena fine
" pari, or azygos, as far as the fifth vertebra
" thoracis* where it is hid by the azygos, as this
" vein rifes forward to join the cava defcendens ;.
" after which the duct pafTes obliquely over to the
" left fide under the cefophagUs, aorta defcendens,
" and great curvature of the aorta, until it reaches
** the left carotid, ftretching farther towards the
" left internal jugular, by a circular turn, whofe
" convex part is uppermoft : at the top of this arch
" it fplits into two for one half line, the fuperior
" branch receiving into it a large lymphatic from
" the cervical glands. This lymphatic appears, by
" blowing and injections, to have two valves ;
" when the two branches are united, the duct con-
" tinues its courfe to die internal jugular, behind
44 which h defcends, and immediately at the left
M ' "fide

170 VASALACTEA.

" fide of the inicrtion of this vein, enters the fu-
" perior and pofterior part of the left fubclavian,
" whofe internal membrane duplicated forms a fe-
" milunar externally convex valve that covers two
" thirds of the orifice of the duct. Immediately
" below this orifice a cervical vein from the muf-
" culi fcaleni enters the fubclavian. The thin coat.
" and valves, commonly ten or twelve, of this duel:,
" are fo generally known, I need not mention them.
" In my notes I find little variation in the recep-
" taculum, only its different capacities in different
" fubjects, and fometimes more ducts concurring
" in the formation of it. The diameter of the duel:
" varies in molt bodies, and in the fame fubjecf. is
" uniform, but frequently fudden enlargements- or
" facculi of it are obiervable. The divifions which
" authors mention of this duct within the thorax
" are very uncertain. In a woman I diffected lafl
" fummer, at the eighth vertebra thoracis, one
" branch climbed over the aorta, and about the
" fifth vertebra flipped back again under that artery*
" to the other branch, which continued in the or-
" dinary courfe. Laft winter I found this duct of
" a man difcharging itfelf entirely into the right
" fubclavian vein. The precife vertebra, where it
" begins to turn towards the left, is alfo uncertain.
" Frequently it does not fplit at its fuperior arch ;
" in which cafe a large faccus is §c ,ear its aper-

" ture into the fubclavian v v^ ally it has

" but one orifice, thoi 1 uave feej A in one

4 body,

VASA LACTEA. i 7 t

ci body, and three in another ; nay, fometimes it
" divides into two under the curvature of the great
" artery ; one goes to the right, another to the left
" fubclavian ; this however is very rare. The lym-
" phatic, which enters the fuperior arch, is often
" fent from the thyroid gland.'*

Suppofing there ordinarily pafTes five pounds
of chyle in a day through the latteals, and that
four ounces of this only are added to the blood
(though it may be any other quantity, for aught I
know) and that a man neither decreafes or increas-
es during this time, then all the reparations from
the fluids and folids muft be juft five pounds ; four
ounces of which muft be thofe fluids and particles
of folids, which are become unprofitable ; and the
remaining four pounds twelve ounces will ferve as a
vehicle to carry the four ounces off: fo that we fee
for what reafon more fluids are carried into the
blood than are to be retained there, and how the
body is by the fame means both nourifhed and pre-
ferred in health.

M2 CHAR

172 PLEURA, MEDIASTINUM,

CHAP. VII.

Of the Pleura, Mediastinum, Lungs,
Pericardium, and Heart.

• Jl LEURA is a fine membrane which lines the
whole cavity of the thorax, except on the dia-
phragm, which is covered with no other than
its own* proper membrane, t The back part of it
is extended over the great veffels, like the perito-
naeum ; and in regard this membrane paries partly
under thefe veflels, as the peritonaeum does in the
abdomen, they may be faid to lie in a duplicaturc
of it ; it ferves to make the infide of the thorax
fmooth and equal.

• Mediaftinum divides the thorax lengthways,
from the fternum to the pericardium and pleura,
which is a very fhort fpace, but in many brutes
very confiderable. ♦ It divides into two in men, but
in brutes it is fmgle ; it divides the thorax not ex-
actly in the middle, but towards the left fide, and
is fo difpofed, that the two cavities, into which it
divides the thorax, do not end toward this mem-
brane in an angle, but a fegment of a circle ; it
hinders one lobe of the lungs from incommoding
the other, as in lying on one fide the uppermoft
might do ; and prevents the diforders of one lobe of
the lungs from affecting the other.
- The lungs are compofed of two lobes, one feated
on each fide of the mediaftinum ; each of which

lobes

and LUNGS. 173

lobes arc fubdivided into two or three lobules,
which are moil diftindly divided in fuch animals
as have mod motion in their backs, for the fame end
that the liver is in the fame animals..- They are each
compofed of very fmall cells, which are the ex-
tremities of the afpera arteria or bronchos. The
figure of thefe cells is irregular ; yet they are fitted
to each other fo as to have common fides, and leave
no void fpace. Into thefe cells the blood vefiels dis-
charge a large quantity of lymph, or materia per-
fpirabilis, which at once ke§ps them from being dri-
ed by the air, and makes a large and neceiTary dif-
charge from the blood, as has already been obferv-
ed upon the fubj eel: of perfpiration through the fkin.
Dr. Willis has" given a very particular defcription
of the inner texture of the lungs, but it is only im-
aginary and falfe, as he, and they who have copied
his cuts and defcriptions, could not but have known,
if they had ever made the leaft inquiry into the lungs
of any animal ; nor is his account of the lymphat-
ics on the furface of the lungs, at all more true
than that of their texture. In the membranes
of thefe cells are diftributcd the branches of the
pulmonary artery and vein. The known ufes of
the air's entering the lungs, are to be inflrumental
in fpeech, and to convey effluvia into the nofe, as
it panes for the fenfe of fmelling ; but the great
ufe of it, by which life is preferved, I think we
do not underftand. By fome the force of the air is
thought to feparate the globuli of the blood that

have

i 7 4 LUNGS.

have cohered in the flow circulation through the
veins ; and this opinion feems to be favoured bf
the many instances of polypufes, which are large
concretions of the globuli of the blood, found in
the veins near the heart, and in the right auricle
and ventricle of the heart ; and their being fo feldom
foun,d in the pulmonary veins, or in the left auricle
or ventricle of the heart, or in any of the arteries ;
but if it is true that, while the blood pafles through
the lungs, many cohering globuli are feparated, yet
it remains to be proved that thefe feparations are
made by the force of the air. Dr. Keil has com-
puted the force of the air in the ftrongeft exfpira-
tions againft the fides of all the veficles, to be equal
to fifty thoufand pound weight ; which though we
mould grant, we mall flill find the moment of the
air in the lungs exceeding final! in any fmall fpace.
For the velocity with which the air moves in the
lungs is as much lefs than that with which it moves
in the wind-rpipe, as the .fquare of a fecYion of the
cells in the lungs is greater than the fquare of a fec^
tion of the wind-pipe j and therefore if the fquare
of all the extreme blood-veffels in the lungs do not
bear a greater proportion to the fquare of the large
pulmonary veffels than the fquare of the cells do
to the wind-pipe, and if the blood in thefe large vef-*
fels moves as fail as the air in the wind-pipe, then the
blood moving iri the fmalleft veffels of the lungs
with a velocity equal to that of the air in the cells,
the blood will have as much more attrition from

the

LUNGS. 175

the power that moves it in its own veffels, than the
air can give upon them, as blood is heavier than
air. Beiides, air preffing equally to all fides, and
the globuli of the blood fwimming in a fluid ; this
preffure, be it what it will, I think, can be of lit-
tle ufe to make fuch reparations. Indeed it may
be objected that the greateft preffure is in exfpira-
tion, yet that furely cannot be very great, while
the air has fo free a paffage out of them. Others
have thought, that the air enters the blood-veffeis
from the cells in the lung?, and mixes with the
blood ; but this opinion, however probable, wants
fufficient experiments to prove it ; air being found
in the blood, as it certainly is, is no proof of itl
entering this way, becaufe hTmay enter with the
chyle : nor is the impoffibiiity whi eh has been
urged of its entering at the lungs without the blood
being liable to come out the fame way into the ve-
ficles-of the lungs, a good argument to tlie contra-
ry ; for if a pliable dud panes between the mem-
branes of a veifel, through a fpace greater than
the fquare of its orifice, no fluid can return, becaufe
the preffure which mould force it back will be
greater againft the fides of that duel: than its orihee ;
Which is the cafe of the bile-duel entering the duo-
denum, and the ureters entering the bladder. I
think the moft probable argument for the air's en-
tering into the blood by the lungs, or rather fome
particular part of the air, may be fetched from a
known experiment of each man in a diving bell

wanting

lyS LUNGS.

wanting near a gallon of frefh air in a minute ; and
if preffure only was wanted in this cafe, they often
defcend, till the preffure of the air is three or four
times what it is upon the furface of the earth, with-
out any advantage from that preffure ; and animals
dying fo foon in air that has been burnt, and their
being fo eafily intoxicated by breathing air much
impregnated with fpirituous liquors, are alfo argu-
ments of a paffage this way into the blood. Befides,
if preffure of the air in the cells of the lungs is the
only ufe of it, I do not fee but enough of that may
be had while a man is hanging, if the mufcles of
the thorax do but act upon the air which was
left in the thorax when the rope was firft fixed,
and yet death is brought about by hanging no other
way than by interrupting of the breath, as I have
found by certain experiments. Dr. Drake has
endeavoured to fhew, that the ufe of refpiration is
to affift the fyftole of the heart ; but this ufe re-
quires that the fyftole and diaftole of the heart
fhould keep time with exfpiration and infpiration,
which is contrary to experience. The lungs of
animals, before they have been dilated with air, are
fpecifically heavier than water ; but upon inflation
they become fpecifically lighter, and fwim in wa-
ter ; which experiment may be made to difcover
whether a dead child was itill born, or not ; but if
the child has breathed but a little, and the experi-
ment is made long after, the lungs may be collapfed
and grow heavier than water, as I have experiment-
ed.

PERICARDIUM and HEART. 177

ed, which may fometimes lead a man to give a
wrong judgment in a court of judicature, but then
it will be on the charitable fide of the queftion.
Adhefions of the lungs to the pleura are in men fo
common, that I know not how to call it a difeafe ;
they being found fo more or lefs in mod adult
perfons, and without any inconvenience, if the
lungs are not rotten.

• Pericardium, or heart-purfe, is an exceeding
ftrong membrane which covers the heart ; its
fide next the great vefTels is partly connected to
them, and partly to the bafis of the heart, but,
I think, not properly perforated by thofe vefTels ;•
and its lower fide is infeparable from the tendinous
part of the diaphragm, but not fo in brutes, in
fome of which there is a membranous bag between
it and the diaphragm, which contains a lobule of
the lungs. It inclofes all the heart to its bafis ;
its ufes are to keep the heart in its place, without
interrupting its office, to keep it fit>m having any
friction with the lungs, and to contain a liquor
to lubricate the furface of the heart, and abate its
friction againft the pericardium,
. The heart is a mufcle of a conic figure, with
two cavities or ventricles ; its bafis is fixed by the
vefTels going to and from it, upon the fourth and
fifth vertebrae of the thorax ; its apex, or point,
is inclined downward and to the left fide, where
it is received in a cavity of the left lobe of the
lungs, as may be obferved,the lungs being extended

with

178 HEART.

with air. - This incumbrance on the left lobe of the
lungs, I imagine, is the caufe of that fide's beino;
moft fubject to thofe pains which are ufually called
pleuritic, which I have ever found upon differing
of them to be inflammations in the lungs.
♦ At the bafis of the heart, on each fide, are fitu-
ated the two auricles to receive the blood ; the right
from the two vena? cava?, and the left from the pul-
monary veins ;» in the right, at the meeting of the
cavae, is an eminence called tuberculum Loweri,
which directs the blood into the auricle ; immedi-
ately below this tubercle, in the ending of the cava
afcendens, is the vefligium of the foramen ovale
(vid. chap. Of the foetus ;) and near this, in the
auricle, is the mouth of the coronary veins. Both
auricles are ftrengthened by mufcular columnar, like
the ventricles. The left is much lefs than the right ;
but the difference is fupplied by a large mufcular
cavitv, which the veins from the lunes afford in that
place. The fide's of this mufcular cavity are thicker
than the fides of the right auricle, in about that
proportion, in which the left ventricle of the heart
is ftronger than the right ; their ufes being to re-
ceive blood from the veins that lead to the heart,
and prefs it into the ventricles, a ftrength in each au-
ricle proportionable to the ftrength of the ventricle
that it is to fill with blood, feems neceffary : and
this different thicknefs of the coats of the auricles
makes the blood in the left, which is thicker!, ap-
pear through it of a paler red ; but when it is let

out

HEART. 179

out of the auricles, it appears alike from both; which
they would do well to examine, who affirm the
blood returns from the lungs of a more florid col-
our than it went in ; and offer it as an argument
of the blood's being mixed with air in the lungs.
The ventricles or cavities in the heart which receive
the blood, are hollow mufcles, or two cavities in
one mufcle, whole fibres interfecr. one another, fo
as to make the preffure of the heart upon the blood
more equal and effectual, and are alio lefs liable to
be feparated than they would have been, if they had
lain in one direction. Both thefe cavities receiv-
ing the fame quantities of blood in the fame times,
and always acting together, muft be equal in frze,
if they equally difcharge what they contain at every
fyftole, as I doubt not but they do • neverthelefs
the left appears lefs than the right, it being found
empty in dead bodies, and the right ufliaily full of
blood ; which made the ancients think the veins
and the right ventricle only were for the blood to
move in, and that the left and the arteries contain-
ed only animal fpirits. The left ventricle is much
the thickeft and ftrongeft, its o!Hce being to drive
the blood through the whole body, while the right
propels it through the lungs only. Over the en-
trance of the auricles in each ventricle, are placed
valves to hinder the return of blood while the heart
contracts, Thofe in the right ventricle are named
tricufpides, thofe in the lefuaaitralcs. One of thefe
laft feems to do further fervice, by covering the

m

mouth

180 HEART.

mouth of the aorta while the ventricle nils ; which
fuffering none of the blood to pafs out of this ven-
tricle into the aorta before the ventricle ads, it will
, be able to give greater force to the blood than it
otherwife might have done ; becaufe a greater quan-
tity of blood more fully diftending the ventricle,
and making the greater refiftance, it will be capa-
ble of receiving the greater imprefTed force from
the ventricle ; and if the blood is no way hindered
in the right ventricle from getting into the pulmo-
nary artery, while the ventricle dilates, as it is in the
left, the left then may be fomewhat bigger than
the right, if they both empty themfelves alike in
. every fyftole. Though the auricles of the heart
are equal to each other, and the two ventricles alfo
equal or nearly equal, yet the auricles are not fo
large as the ventricles ; for the ventricles contain
not only all the blood which flowed from the veins
into the auricles, daring the contraction of the heart,
but alfo that which flows (which will be directly
into the heart) while the auricles contract, and the
ventricles dilate; which leads us to the exact knowl-
edge of the ufe of the auricles. If the fyftole and
diaftole of the heart are performed in equal times,
then the auricles muft be half the fize of the ven-
tricles ; or whatever proportion the fpace of time
of the fyftole of the heart bears to the fpace in
which the fyftole and diaftole are both performed,
that proportion will the cavities of the auricles
bear to the cavities of the ventricles. The inner

fibres

HEART. 181

fibres of each ventricle are difpofed into fmall cords,
which are called columnar : from fome of thefe
Hand fmall portions of fleih called papilla? ; thefe
papillae are tied to the valves by (lender fibres,
whereby they keep the valves from being preffed
into the auricles by the action of the blood againfl
them in the fyftole of the heart : and when that
is over, the blood flowing in between them opens
them, as the prefTure of blood on the other fide
fhuts them in the fyftole. For the courfe of the
blood through this part, vid. chap. Of the courfe
of the aliment and fluids. In the beginning of
each artery from the heart are placed three valves,
which look forward, and clofe together to hinder
a regrefs of blood into the ventricles. Thofe in
the pulmonary artery are named figmoidales, thofe
in the aorta, femilunares. For the canalis arteri-
ofus, vid. chap. Of the foetus.

In a boy I found a great quantity of pus in the
pericardium, and the bafis of the heart ulcerated.
In perfons that have died of a dropfy, I have ufu-
ally obferved the heart large, its. fibres lax, and the
veffels about it immoderately diftended, and poly-
pufes fometimes in both auricles and ventricles,
and in the large veins ; but more frequently in
the right auricle and ventricle. Mr. Pile has
prepared a heart thus difeafed, whofe circumfer-
ence from the vertex round the bafe of the auri-
cles meafures twenty-four inches and a quarter,
and round the bafe of die ventricles feventeen

inches

:8a HEART.

inches and a half. I differed a man that died
tabid, in whom the pericardium univerfally ad-
hered to the heart, and a portion of the mufcular
part of the heart was offified as large as a iix-
pence. The beginning of the aorta is frequently
feen offified, efpecially in aged pcrfons. In a wom-
an that died of a dropfy, I found the valves of the
aorta quite covered with chalk-ftones, which not
fufFering the valves to do their office, the left
ventricle of the heart was conilantly overcharged
with blood, and diftended to above twice its nat-
ural bignefs, which, I imagine, deftroyed the econ-
omy of the body, and occafioned the dropfy.

Upon opening the body of a perfon, who died
with exceffive palpitations of the heart and un-
even pulfe, which began after very hard drinking,
in extreme hot weather, fome years before, I
found about ten inches of the aorta neareft the
heart diftended three times its natural diameter ;
and in a man. one hundred and three years old, I
found the fame part of the aorta extended twice*
its natural capacity, without any fymptom of fuch
a diforder when living.

CHAP.

ARTERIES and VEINS. ilj

CHAP. VIII.

Of the Arteries and Veins.

hfc ROM the right ventricle of the heart arifes the
pulmonary artery, which foon divides into two
branches, one to each lobe of the lungs ; then
they fubdivide into fmaller and fmaller branches,
until they are diftribuied through every part of the
lungs. From the extreme branches of the pulmo-
nary artery arife the fmall branches of the pulmo-
nary veins ; which, as they approach the left auri-
cle of the heart, unite in fuch a manner as the pul-
monary artery divides going from the heart, only
that the veins enter the mufcular appendix of the
left auricle in feveral branches, and the blood being
brought back from the lungs by thefe veffels to the
left auricle and ventricle of the heart, it is from the
left ventricle of the heart thrown into the aorta..
• Aorta, or great artery, arifes from the left
ventricle of the hearty and deals cmt branches to ev-
ery part of the body. The firft part of this vefTel
is called aorta afcendens ; it pafTes over the left
pulmonary artery, and veins, and branch of the af-
pera arteria, and being reflected under the left lobe
of the lungs, it commences aorta defcendens ; which
name it keeps through the thorax and abdomen,
where it pafTes en the left fide of the fpine, till its

divifion

x84 ARTERIES and VEINS.

divifion into iliac arteries between the third and
fourth vertebras of the loins. .
* From under two of the femilunar valves of the
aorta, which is ere it leaves the heart, arife two
branches (fometimes but one) which are bellowed
upon the heart, and are calied coronarise cordis*
From the curved part of the aorta, which is about
two or three inches above the heart, arife the fub-
clavian and carotid arteries ; the right fubclavian
and carotid in one trunk, but the left fingle. . By
fome authors thefe veffels have been defcribed in
a different manner ; but I believe their defcrip-
tions were, for want of human bodies, taken from
brutes j> for I have never yet feen any variety in
thefe veffels in human bodies, though I have in
the veins nearer the heart : and indeed there feems
to me to be a mechanical reafon for their going off
in the manner here defcribed, in human bodies ;
for the right fubclavian and carotid arteries necef-
farily going off from the aorta at a much larger an-
gle than the left, the blood would move more free-
ly into the left than the right, if the right did not
go off in one trunk, which gives lefs friction to the
blood than two branches equal in capacity to that
one ; fo that the advantage the left have by going
off from the aorta at much acuter angles than the
right, is made up to the right by their going off at
firft in but one branch.

• The carotid arteries run on both fides the la-
rynx to the fixth foramina of the fcull, through

which

ARTEP.IES and VEINS. 185.

Which they enter to the brain ;. but as they pafs
through the neck, they detach branches to every
part about them, which branches are called by the
names of the parts they are bellowed upon ; as,
laryngeal, thyroidex, pharyngeal, linguales, tem-
porales, occipitales, faciales, &c. but jufl before they
enter the fixth foramina of the fcull, they each
fend a fmall branch through the fifth foramina to
that part of the dura mater which contains the
cerebrum. It is thefe arteries which make
thofe impreflions which are conltantly obferved on
the infide of the ofla bregmatis : thefe branches,
Mr. Monro obferves, oftener arifefrom the tempo-
ral arteries. The internal carotids fend two branches
to the back part of the nofe, and feverai branches
through the firft and fecond foramina of the fcull
to t the face and parts contained within the orbits of
the eyes, and then piercing the dura mater, they
each divide into two branches, one of which they
fend under the falx of the dura mater, between the
two hemifpheres of the brain, and the other be-
tween the anterior and pofterior lobes. Thefe
branches take a great many turns, and divide into
very fmall branches i^n the pia mater before they en-
ter the brain, as if the pulfe of larger arteries would
make too violent an impreffion on fo tender and
delicate a part. And perhaps it may be from an
increafe of the impulfe of the arteries in the brain,
which ftrong liquors produce, that the nerves are
fo much interrupted in their ufes throughout the

N whole

iS6 ARTERIES and VEINS.

whole body, when a man is intoxicated with drink-
ing ; and may it not alio be from a like caufe that
men are delirious in fevers ? Befides thefe two ar-
teries, viz. the carotids, the brain has two more,
called cervicales, which arife from the fubclavian
arteries, and afcend to the head through the fora-
mina, in the tranfverfe proceffes of the cervical
vertebrae, and into the fcull through the tenth or
great foramen. Thefe two arteries uniting foon
after their entrance, they give off branches to the
cerebellum, and then palling forward, divide and
communicate with the carotids ; and the carotid ar-
teries communicating with each other, there is an
entire communication between them all ; and thefe
communicant branches are fo large that every one
of thefe four great veffejs, with all their branches,
may be eafily filled with wax through any one of
them.

• The fubclavian arteries are each continued to
the cubit in one trunk, which is called axillaris as
it panes the arm-pits, and humeralis as it panes by
the infide of the os humeri, between the mufcles
that bend and extend the cubit.* From the fub-
clavians within the breafl arife the arterias mamma-
rix, which run on the infide of the fternum, and
lower than the cartilago enfiformis. Soon after the
arteria humeralis has paffed the joint of the cubitf*
it divides into two branches, called cubitalis fuperi-
or, and cubitalis inferior ; which latter foon fends off
a branch, called cubitalis media, which is bellowed

upon

ARTERIES and VEINS. 187

upon the mufcles feated about the cubit. The
cubitalis fuperior pafles near the radius, and round
the root of the thumb, and gives one branch to
the back of the hand, and two to the thumb ; one
to the firft finger and a branch to communicate
with the cubitalis inferior. The cubitalis inferior
pafies near the ulna to the palm of the hand, where
it takes a turn, and fends one branch to the outfide
of the little finger, another between that and the
next finger, dividing to both, another in the fame
manner to the two middle fingers, and another to
the two fore fingers. Thefe branches which are
beftowed on the fingers run one on each fide ojf
each finger internally to the top, where they have
fmall communications, and very often there is a
branch of communication between the humeral
and inferior cubital arteries. This communicant
branch is fometimes very large, and liable to be
pricked by carelefs or injudicious blood-letters, in
bleeding in the bafilic vein, immediately under
which, as far as I have been able to obferve, this
branch always lies. Mr. Monro has found the
fubclavian artery divided, in one fubjecl, into two,
the exterior of which formed the cubitalis fuperi-
or, and the inner artery, the cubitalis inferior ; from
which ftructure he accounts for the fuccefs in the
Operation of the aneurifm fometimes performed
above the cubit. When the operation for an
aneurifm is made upon this communicant branch,
it is found neceffary to tie it on both fides of the
N 2 orifice,

i88 ARTERIES and VEINS.

orifice, becaufe the blood is liable to flow freely into
it either way.

• From the defcending aorta on each fide is fent
a branch under every rib, called intercofialis, and
about the fourth vertebra of the back it fends off
two branches to the lungs, called bronchi ales, which
are fometirnes both given off from the aorta, fome-
times one of them from the intercoftal of the fourth
jib on the right fide y and as the aorta paffes under
the diaphragm, it fends two branches into the dia-
phragm, called arterisc phrenic??, which fome-
tirnes rife in one trunk from the aorta, and fome-
tirnes from the cceliaca ; but oftener the right from
the aorta, and the left from the cceliaca. Immedi-
ately below the diaphragm arifes the cceliac artery
from the aorta ; it foon divides into feveral branch-
es, which are bellowed upon the liver, pancreas,
fpleen, flomach, omentum, and duodenum. Thefe
branches are named from the parts they are bellow-
ed on, except two that are bellowed upon the ftom-
ach, which are called coronaria fuperior and infe-
rior, and the branch bellowed upon the duodenum,
which is named inteftinalis. At a very fmall dis-
tance below the arteria cceliaca from the aorta arifes
the mefenterica fuperior, whofe branches are bellow-
ed upon all the inteflinum jejunum and ilium,part of
the colon, and fometirnes one branch upon the Y\vex0
A little lower than the fuperior mefenteric artery
arife the emulgents, which are the arteries of the kid-
neys. And a little lower than the emulgents, for-
ward

ARTERIES and VEINS. 189

ward from the aorta, arife the arteria* fpermatica? ;
for which, vid. chap. Of the parts of generation
in men. Lower laterally the aorta fends branches
to the loins, called lumbales ; and one forward, to
the lower part of the colon and the redfcum, called
mefenterica inferior. Between the arteria cceli-
aca, mefenterica fuperior and inferior, and the
branches of each near the guts, there are large
communicant branches- to convey the blcod from
one to another, when they are either compreiTed
by excrements, or from any other caufe.

• As foon as the aorta divides upon the loins, it
fends ofF an artery into the pelvis upon the os fa-
crum, called arteria facra, and the branches the
aorta divides into are called iliacse, which in about
two inches fpace divide into external and internal..
The iliacse interna? firft fend off the umbilical ar-
teries, which are dried up in adult bodies, except at
their beginnings, which are kept open for the col-
lateral branches on each fids, one to the bladder,
and one to the penis in men, and in women the
uterus : the reft of thefe branches are be (lowed up-
on the buttocks and upper parts of the thigha.
The iliacse externa mn over the offa pubis into
the thighs ; and as they pafs out of the abdomen
they fend off branches, called epigaftricse to the
^fore part of the integuments of the abdomen un-
der the recti mufcles. And the epigaflric arteries
fend each a branch into the pelvis, and through
the foramina of the offa innominata to the mufcles

thereabouts*

190 ARTERIES and VEINS.

thereabouts. • As foon as the iliac artery is patted
out of the abdomen into the groin it is called in-
guinalis, and in the thigh cruralis, where it fends.
a large branch to the back part of the thigh ; »but
the great trunk is continued internally between
the flexors and extenfors of the thigh, and palling
through the infertion of the triceps mufcle into the
ham, it is there called poplitea ; then below the
joint it divides into two branches, one of which is
called tibialis antica ; it pafTes between the tibia
and fibula to the fore part of the leg, and is be-
llowed upon the great toe, and one branch to the
next toe to the great one, and another between
thefe toes, to communicate with the tibialis pofli-
ca ; which artery, foon after it is divided from the
antica, fends off the tibialis media, which is be-
llowed upon the mufcles of the leg ; the tibialis
poftica goes to the bottom of the foot and all the
lefTer toes. The tibialis antica is difpofed like the
cubitalis fuperior ; ; the poftica like the cubitalis in-
ferior ; and the medise in each have alfo like ufes.
Thefe arteries which I have defcribed, are uniform
in moil bodies, but the lefler branches are diflrib-
uted like the branches of trees, in fo different a
manner in one body from another, that it is highly
probable no two bodies are exactly alike, nor the
two fides in any one body. jk

I have once feen a rupture of matter, and once
of blood and matter, which flowed out of the ab-
domen into the fore part of the thigh, through the

fame

ARTERIES and VEINS. 191

fame paffage at which the iliac artery goes out of
the abdomen.

* The veins arife from the extremities of the ar-
teries, and make up trunks which accompany the
arteries in almoft every part of the body, and have
the fame names in the feveral places which the ar-
teries have, which they accompany.. The veins of
the brain unload themfelves into the finufes (vid.
chap. Of the dura and pia mater) and the finufes
into the internal jugulars and cervicals ; and the
internal jugulars and cervicals into the fubclavians,
which joining, make the cava defcendens. The
internal jugulars are feated by the carotid arteries,
and receive the blood from all the parts which the
carotids ferve, except the hairy fcalp and part of
the neck, whofe veins enter intft the external ju-
gulars, which run immediately under the mufcuius
quadratus gena?, often two on each fide. The cer-
vical veins defcend two through the foramina in the
tranfverfe proceffes of the cervical vertebras, and two
through the great foramen of the fpine, and one on
each fide the fpinal marrow ; thefe join at the low-
eft vertebra of the neck, and then empty into the
fubclavians, and at the interftices of all the vertebra;
communicate with one another.

• The veins of the limbs are more than double
the number of the arteries, there being one on each
fide each artery, even to the fmalleft branches that
we can trace, befides the veins which lie immedi-
ately under the fkin. , Thofe which accompany the

arteries,

192 ARTERIES and VEINS.

arteries, have the fame names with the arteries ; thofe
which run immediately under the (kin on the hack
of the hand, have no proper names ; they run from'
thence to the bend of the elbow, where the uppcr-
moft is called cephalica, the next mediana, the next
bafilica. Thefe all communicate near the joint of
the elbow, and then fend one branch which is
more directly from the cephalica, and bears that
name until it enters the fubclavian vein ; it paffes
immediately under the fkin, in moft bodies, be-
tween the flexors and extenfors of the cubit, on the'
upper fide of the arm. The other branches joining,
and receiving thofe which accompany the arteries
of the cubit, they pafs with them by the artery
of the arm into the fubclavian vein. The external
veins have frequent communications with the in-
ternal, and are always fulleft when we ufe the
moft exercife ; becaufe the blood being expanded
by the heat which exercife produces, it requires the
veffels to be diftended ; and the inner veffels being
compreffed by the actions of the mufcles, they
cannot dilate enough ; but thefe veffels being feat-
ed on the outfides of the mufcles, are capable of
being much dilated ; and this feems to me to be the
chief ufe of thefe external veffels. The cephalic
vein, as it runs up the arm, is very vifible in moft
men, but in children is rarely to be feen ; there-
fore great care fhould be taken not to wound it in
the cutting of iffues in children's arms ; and I know
no way to be fure of avoiding it, but by cutting the

iffue

ARTERIES and VEINS. 193

ifiue more externally than is ufual in men, which
may be done without any inconvenience.
• In the thorax, befides the two cavae, there is a
vein called azygos, or vena fine pari ; it is made up
of the intercoftal, phrenic, and bronchial veins,
and enters the defcending cava near the auricle,
as if its ufe was to, divert the defcending blood
from falling too directly upon the blood in the
afcending cava, and direct the blood of the de-
fcending cava into the auricle. ,
» In the abdomen (befides the cava afcendens and
the veins which are named like the arteries, viz.
the emulgents from the kidneys, the lumbal and
fpermatic veins, the facra, iliac, and hypogaftric
veins) there is one large one called vena porta!,,
whofe branches arife from all the branches of the
cceliac and two mefenteric arteries, except thofe
branches of the* cceliac and fuperior mefenteric,
which are beftowed on the liver, and uniting in
one trunk enters the liver, and is there again dis-
tributed like an artery, and has its blood collected
and brought into the cava by the branches of the
cava in the liver ; this vein being made ufe of in-
ftead of an artery to carry blood to the liver, for
the feparation of bile. It moves here about eight
times flower than in the arteries hereabouts ; and
this flow circulation being mppofed neceflfary, I
think, there feems no other way fo fit to procure
it ; for if an artery had been employed for this ufe,
and been thus much dilated in fo fhort a palfage,

the

i 9 4 ARTERIES and VEINS.

the blood would not have moved fo uniformly in
it, but fafter through its axis than near its fides ;
and befides, it is very probable that the blood in
this vein, having been rirft employed in nourifh-
ing feveral parts, and having through a long fpace
moved flowly, may be made thereby fitter for the
feparation of bile, than blood carried by an artery
dilated to procure a circulation of the fame velocity
with that in this vein.

In the leg the veins accompany the arteries in
the fame manner as in the arm, the external veins
of the foot being on the upper fide, and from them
is derived one called faphena, which is continued
on the infide of the limb its whole length, and
has feveral names given it from the feveral places
through which it pafTes,

• The arteries have three coats ; a middle muf-
eular, and an external and internal membranous.
The veins are faid to have the fame ;♦ the internal
coat of an artery may be pretty eafily feparated, but
not the external ; and though the veins have muf-
cular fibres, yet I could never feparate any one dis-
tinctly into three coats ; and in the infide of the
veins there are many valves, efpecially in the low-
er limbs, to hinder any reflux of the venal blood,
which otherwife would have happened from the
frequent actions of the mufcles on the outfides of
the veins ; and both the arteries and veins, as they
run in the infide of the limb, or as they are dif-
perfed in parts that fuffer great extenfions, as the

ftomach,

ARTERIES and VEINS. 195

ftomach, guts, and uterus, they are curved fo
much as that when thefe parts come to be diftend-
ed, they may comply with thofe diftenfions by only
being ftraitened, and fo preferved from being
ftretched, which would leffen their diameters. The
fmall arteries near the heart go off from the large
trunks at obtufe angles, farther at lefs obtufe angles,
ihen at right angles, farther ftill at acute angles,
and near the extremities at very acute angles, be-
caufe the blood in the veffels far from the heart
moving with lefs velocity than the blood in the
veffels near the heart, the blood in the collateral
branches more remote from the heart wants the
advantage of a directer courfe ; and becaufe a very
large branch arifmg out of another, might weaken
too much the fides of the veffel it would arife from,
that inconvenience is prevented by increasing the '
number, and fo leffening the fize of the collateral
branches, where otherwife one large branch would
have ferved better ; as in the going off of the fub-
clavian and carotid arteries, which might have gone
off for fome fpace in one trunk j but this median-
ifm is more evident in the going off of the arteria
coeliaca and mefenterica fuperior, And the fmaH
arteries always divide" fo as that the lcffer branch
may lie leaft in the direction of the blood flowing
into them, which makes the blood flow moll freely
into that branch that hath farther!: to carry it ; and
the fmaller branches arife more or lefs obliquely
from the fides of other arteries, according to the

proportion

ig6 ARTERIES and VEINS.

proportion they bear to the arteries they arife from,
becaufe an artery comparatively large arifing ob-
liquely from the fide of another, would make an
orifice in that it arifes from too large, and weaken
it. And both thefe ends are at once brought about,
by making the arteries, that give off the branches,
bend more or lefs toward the branches they give
off, according to the comparative magnitude of the
branches given off.

Borelli has computed the force which the
heart exerts at every fyftole, to be equal to three
thoufand pounds weight, and the force which all
the arteries exert at every fyftole, to be equal to
fixteen thoufand pounds weight, and that they to-
gether overcome a force equal to an hundred and
thirty-fix thoufand pounds weight ; and Dr. Keie
has computed that the heart in every fyftole exerts
a force not exceeding eight ounces. The firft com-
putation was made by comparing the heart with
other mufcles,whofe power to fuftain a weight could
be beft determined j and the latter was made from
the velocity of the blood moving in an artery :
therefore if we confider that Boreeli's way of
computing led him to find out the abfolute force of
the heart, and Dr. Keil's the force which the heart
ufually exerts, perhaps thefe very different compu-
tations may be accounted for y for if the force of
the heart, which is conftantly exerted, mould, com-
pared with any other mufcle, be but in a reciprocal
proportion to the frequency of their actions, and

the

ARTERIES and VEINS. 197

the importance of their ufes ; may not the heart
very fitly have a force vaftly greater than ufually it
exerts, becaufe it is always in action, and mufl be
able to exert a certain force in the loweft flate of
health ? What force the heart ever exerts in a grown
man, I cannot fay ; but it mull be lefs in each ven-
tricle than is •fufficient to buril the valves, which,
hinder the blood from returning into the auricles
out of the ventricles, or than is fufficient to break
thofe threads by which thefe valves are tied to the
papillse. In a dog, I found the force which the
heart would exert, would not raife to one foot per-
pendicular height a column of blood through the
aorta afcendens. And when I inject the arteries of a
child, I find a force exceeding little will throw wa-
ter through all the velTels, with a velocity equal to
that with which the blood moves in thofe veflels
when living. And if the heart, like other mufcles,
can perform the firft part of its contraction with
molt eafe, are not the quick actions of the heart in
hectic fevers owing to its not being able to empty
the ventricles every fyftole, which, I think, will
oblige it to act, ceteris paribus, fo much the often-
er ? For the following ingenious attempt to ac-
count for the fyftole and diaftole of the heart, and
the reciprocal actions of the auricles and ventricles,
I am obliged to Mr. Monro.

" Poftulata, that the action of the mufcles de-
" pends on the influx of blood and liquidum ner-
" vofum into the mufcular fibres, and therefore,

" whenever

198 ARTERIES And VEINS.

" whenever the mufcles are deprived of either or

" both thefe fluids, their action ceafcs ; this a great

" many authors have fully proved by tying and

■ cutting the nerves and arteries that ferve any

" mufcle. That all mufcles are in a conftant ftate

u of contraction as long as the blood and liquidum

" nervofum are freely fupplied to them, which

" feems evident from the Iphincler ani and veficae,

" and from the continued contraction of fuch muf-

" cles, whofe antagonifts are cut afunder, or pa-

" ralytic. That the nerves of the heart run to it

" between the auricles and arteries, and that the

" arterise coronarise rife from the aorta behind the

" valvulae femilunares, both which are evident from

" dhTections. If then both auricles and ventricles

" are ready, upon the firft. communication of mo-

" tion, to contract at the fame time, the ventricles >

" as Dr. Keil well obferves, being ftronger, will

" firft contract:, and hinder the contraction of the

" auricles, which muft be in the mean time much

" dilated by the influx of blood from the veins,

" while the arteries are alfo diftended by the blood

" thrown out of the ventricles ; therefore the car-

" diac nerves lying between the two will be com-

" prefled, and the courfe of the liquids in them ftop-

u ped ; at the fame time the blood that rufhes out

" of the left ventricle into the aorta, pufhes the

" valves of that artery upon the orifices of the ar-

" teriae coronarise, fo that no blood can enter into

" the fubftance of the heart ; thus both caufes of

" contraction

ARTERIES and VEINS. 199

" contraction failing, this mufclc rauft become pa-
" ralytic. The refiftance then to the contraction of
" the auricles being now removed, they will throw
" their blood into the ventricles ; and the impulsion
" of blood into the arteries frOm the heart now alfo
" ceafing, the two great arteries will be conftrict-
" ed : the nerves are therefore now again free from
" compreflion, and the valves of the aorta being
" thruft back upon the mouth of the ventricle, the
" blood enters the artcrise coronarise ; fince the ven-
" tricles are again fupplied with both the liquids
" on which their contraction depends, they mud
" again act. And thus as long as thefe caufes con-
" tinue, their effects muft follow, i. e. as long as
" the creature lives, the heart muft have an al-
" ternate fyftole and diaftole, and the auricles and
" ventricles have reciprocal actions."

If the arteries contract, fuppofe, a fourth part
of the fquares of their diameters at every fyftole, and
if the heart does not throw out a quantity at every
fyftole, equal to the fourth part of the folid con-
tents of all the arteries when dilated, it is evident
the heart does not throw the blood through the
whole arterial fyftem, but into fo much of the ar-
teries neareft the heart, as will contain four times
as much as is thrown out of the left ventricle at
once : and then this portion of arteries throws the
blood forwards and dilates the arteries that lie next,
and fo on : but if the capacities of all the arteries
taken together in their utmoft dilatations, exceed

their

coo ARTERIES and VEINS.

their capacities in their utmoft contractions, j ufl Co
much as the quantity of blood amounts to, which
is thrown out of the left ventricle of the heart at
every iyftole, which I believe is the cafe, then every
contraction of the heart propels the blood through
the whole arterial fyftem, which may be the reafon
why the largeft animals, casteris paribus, have the
floweft puiies and lead vigour in their motions, and
perhaps too for the fame reafon require a lefs pro-
portion of food. The fedtions of all the remoter
veffels being greater than a feclion of the aorta,
the blood will move fo much flower in the leffer
veffels than in the greater, as the feclions of the
leffer veffels taken together exceed the feclion of
the greater veffel or veffels. The ftrength of the
coats of the arteries, if the blood preffed equally
againft the fides of them all, cseteris paribus, ought
to be one to another as their circumferences, be-
caufe fo much as the circumference of one artery
is greater than another, fo much greater preffure
its fides mull fuftain ; but the arteries neareft the
heart, fuftaining the re-aclion of all the arterial
blood, they muft have a ftrength yet greater than
in that proportion ; and the veffels, -both arteries
and veins, the more diftant they are from the
head, the greater proportional ftrength their coats
muft have, becaufe the arterial and venal blood
communicating, they will prefs upon the lower
veffels, with a force proportional to the perpendic-
ular altitude of blood above, which will be that of

the

ARTERIES and VEINS. 201

the perpendicular altitude of the whole body ; for
though the afcending blood of the arteries may be
faid not to prefs upon the defcending, becaufe it
moves another way, neverthelefs, it being thrown
from the heart into one common vcflel, which af-
terwards divides, the blood moving both ways com-
municates, and that force which is neceffary to
overcome the natural inclination of the afcending
blood to defcend, will be imprefTed alfo upon the
defcending blood, which is juft the fame with the
weight of the afcending blood ; and the veins both
from above and below communicating at the right
auricle, the preflure in them will alfo be as the
perpendicular altitude of the body. So that the
blood in all the veins and arteries may be compared
to a fluid in a curved tube, in which that part in
one leg exactly balances thauin the other, and both
prefling molt upon thofe parts which are neareft
the centre of the earth. Accordingly we find by
experience, that humours are mod apt to flow to
the loweft parts, and that by laying thofe parts upon
a level with the whole body, this inconvenience is
remedied ; but laying a leg only en a chair does it
but in part, juft fo much as the perpendicular alti-
tude of the body*from that part is mortened. There
is alfo to be confidered concerning the thicknef-
of the coats of the veffcls, that the blood movin
flower in the fmall veflels than in the great, the mo-
ment of the blood againft the fides of a fmall vefTel
will be as much lefs than the moment of the blood
O againft

202 ARTERIES and VEINS.

againft equal parts of a great one, as the velocity of
the blood in aT(taH vefTel is lefs than that in a great
one ; and therefore their coats may alio differ from
the former proportion, as the velocity of the blood
differs. Moft of the fmall veffels in the limbs ly-
ing againft one another are a mutual fupport, and
therefore lefs liable to be dilated or burft than ca-
pillaries, which lie in the thin membranes of cavi-
ties, fuch as in the nofe. Hence thefe, I fuppofe,
are moil fiibjeft to haemorrhages. And if haemor-
rhages of blcod do frequently arife from obftruc-
ti'ons in the minuted veffels, does it not appear how
opium and the bark, if they thin the blood inwardly
taken (as they do moil powerfully when mixed
with it) come to be fo often effectual remedies in
that cafe ? And the coats of the leffer veffels being
proportionably weaker than the great ones, accord-
. ing to the decreafe of the velocity of the blood,
which leffens the moment with which it moves in
them, whenever the blood begins to move in them
with an equal velocity, or greater, as it happen*
after an amputation, when the larger veffels are tied,
the force of the blood fometimes overcomes the
ftrength of the coats of the fmaller veffels, and di-
lates them fo, that thofe veffels which fcarce bled
during the operation, will fometimes bleed after-
wards. And this conftant effort of the blood to
dilate veffels upon the obftructions of others may
caufe thofe throbbing pains which are felt in
wounds when the bleeding is {topped, and in all
-„ m ^^ violent

ARTERIES and VEINS. 203

violent inflammations, until the collateral branches
are dilated, or the tendon of thg -parts otherwife
taken off.

« The extreme branches both of the arteries and
veins have very numerous communications, like
thofe in the ftamina of the leaves of plants, by
which communications the blood that is obftruct-
ed in any veffels may pafs off by other veffels that
are not obftructed ;. and the moment of the blood
in the veffels leffening, and the friction from the
veffels increafmg as it approaches the extremities ;
and as many of the leffer veffels are more expofed
to preffure than any of the large ones, thofe com-
munications in the leffer veffels are therefore made
more numerous. By means of thefe communica-
tions, the blood circulates in a limb that has had
part amputated, and into any veffels that have
been feparated from the trunks that fupplied
them, which otherwife muft have mortified for
want of nouriihment, and with them, for the
fame reafon, all the branches that arife from fuch
feparated veffels ; and I can difcern no other way
than bv thefe communications, that the fluids

contained in<a large inflammation can fuppurate

into one cavity.

If we inject by the arteries a large quantity of a

coloured fluid, we find all the large veins full of

that liquor before any of the folid parts are" much

coloured with it ; and upon frequent repetitions all

of them much lefs coloured than, I think, might be,

O 2 expected,

204 ARTERIES and VEINS.

expected, if it had gone into all the veflels of the
body ; and I have often thrown wax or tallow,
coloured with vermilion or verdigreafe, throu
all the arteries, and back again through the veins,
even to the heart, every where filling veiTels t
cannot be difcerned without a microfcope •. and all
this without filling or much difcolouring any one
entire part. In viewing with a microfcope the cir-
culation of the blood in the tail of a fifh, the eye
eafily traces arteries to their extremities, and their
return in veins ; yet all the veflels we can fee make
but a fmall part of the whole of what we fee ;
though we are taught that the whole animal body
is a compages of veflels, fuch as we fee : but if it
were fo, I think, we could not well diftinguim any ;
and if the fum of the diameters of all the veflels
we can fee, are to that of the breadths and thick-
nefles of all the reft of the parts, which we fee at
the fame time, taken together, but as one to five,
thefe veflels then are no more than the twenty-
fifth part of what we fee with them. What then
fhall we fuppofe the reft of the tail, and thofe parts
which were fo little tinged, and thofe which were
not filled with wax, in the foregoing experiments,
compofed of ? Are they not competed of veflels
which arife from the arteries, as excretory duels do
in a gland, but terminate in the veins ? And thefe
veflels being only to convey the nutritious juices,
and what elfe may be a proper vehicle for them,
is it not fit the circulation in them fhould be ex-
ceeding

ARTERIES and VEINS. 205

needing flow, that the nutritious particles may ad-
here the ealier to the fibres of the veffels, which
they are to augment or repair ? Befides, if any
whole part was made up of blood veffels, or any
•other veffels with fluids moving fwiftly in them, it
feems to me impoffible, that one part of a limb can
be very cold while another part is hot, if the warmth
cf the parts is owing to the fluids they contain.
And if there are fuch veffels as thefe, the velocity
of the motion of their fluids will not depend upon
any proportion they bear to the veffels they arife
from, but upon the velocity with which their fluids
are feparated from the arteries into them, and the
f ^portion of the fe&ions of all their orifices to
the fum of their own fedions, at any diftance
where we would compare the velocity of their
fluids. And the ftrength of the coats of thefe vef-
fels may not only be as much lefs than the ftrength
of the coats of an artery, as their diameters are
lefs, but alfo lefs in that proportion in which the
velocity of their fluids is lefs, and the motions more
uniform, than the velocity and motion of the blood
in an artery.

. The coats of the veins are much thinner than
thofe of the arteries, comparing veffels whofe fec-
tions are equal, becaufe the blood moving flower
in the veins than in the arteries, it preffes with lefs
moment againft their fides *./ and befides, the blood
in the veins has nearly an equal uniform motion,
but in the arteries a very unequal one ; and that

will

206 ARTERIES and VEINS.

will require a farther difference in the ftrength of
their coats ; for thofe of the arteries muft be equal
to the greateft natural preflure ; and if the arterial
blood propels the venal, that is a farther reafon for
the different ftrength of their coats.

All thefe things being confidered, it appears to
be a difficult thing to determine nearly, what pro-
portion the fluids of an animal body bear to the
folicis, or what proportion the fum of all the mi-
nuted arteries bear to the aorta, without which, I
think, we can neither determine the comparative
velocity of the blood moving in the different veffels,
nor the quantity of blood in any animal body, nor
the time in which the whole mafs of blood, or a
quantity equal to the whole mafs, is flowing through
the heart. But if each ventricle of the heart holds
five ounces of blood, and they are filled and emp-
tied every fyfiole and diaflole, which, I think, is
true, and if eighty pulfes in a minute be allowed
to be a common number, there then flows twenty-
five pounds of blood through each ventricle of the
heart in a minute. Dr. Keil has fhewn that the
fum of all the fluids in a man exceed the fum of
all the folids, and yet the quantity of blood which
all the vifible arteries of a man will contain, is lefs
than four pounds ; and if we may fuppofe all the
vifible veins, including the vena porta?, hold four
times as much, the whole then that the vifible vef-
fels can contain is not twenty pounds; but the whole
that they do contain is but very little more than the

veins

ARTERIES and VEINS. 207

'veins can contain, feeing the arteries are always
found almoft empty in dead bodies ; but how much
the invifible arteries and veins contain, I mean thoie
which contain fuch a compound fluid as is found
in the larger vefTels, I know no way to judge, un-
lefs we knew what proportion thefe veffels bear to
thofe that carry the nutritious juices and ferum (if
there are fuch) without the globuli of the blood.
Ceteris paribus, is not the velocity of the blood in
all animals proportionable to their quantity of
action ; and their neceffity of food alfo in propor-
tion to their quantity of action £ If fo, it appears
how thofe animals which ufe no exercife, and whofe
blood moves extremely flow in the winter, can fub-
fift without any frefh fupplyof food ; while others
that ufe a little more exercife, require a little more
food ; and thofe who ufe equal exercife winter and
fummer, require equal quantities of food at all
times ; the end of eating and drinking being to re-
pair what exercife and the motion of the blood has
deftroyed or made ufelefs j and is not the lefs ve-
locity of the blood in fome animals than in others,
the reafon why wounds and bruifes in thofe ani-
mals do not fo foon deftroy life, as they do in ani-
mals whofe blood moves fwifter ?

I had a patient, whofe mufcles on the infids
of the thigh were torn to pieces with the cramp,
from whence was a vaft efFufion of blood among
the mufcles. The tumor being opened, it was
judged neceflTary to take off the limb. The pa-

tie.nt,

%

2o8 ARTERIES and VEINS.

tient, having a great difcharge from the wound,
was eafy for about ten days ; but the cramp then
returned into the flump with fuch exceffive tor-
ment that he died foon after. I have never heard
but of one other cafe of this kind, which ended in
the fame manner.

When any of the veffels are lacerated by bruifes,
ftrains, or otherwife, without any external wound,
purging (which is of more ufe than one can well
account for) and cooling applications are always
proper to prevent as much as may be extravafations
of blood or ferum ; but the lacerations once healed,
which may be in eight or ten days, and the pain
quite gone, then warm medicines may be applied,
with opium, or fp. cornu cervi (which powerfully
feparate coagulated fluids) to help to attenuate and
thereby diffipate the extravaiated juices.

When the blood-veffels become unable to pre*
fcrve the circulation in the extreme parts, whether
from particular weaknefs in the veffels, or any
other decay, I have always obferved it to be hurtful
to fcarify. It lets out the juices that mould affift
nature to make a feparation of the mortified part ;
nor can it be known in what place we may fifely
amputate till fuch a feparation which teaches us
where it can be fupported, and in any place fhort
of that, an operation will be both ufelcfs and mif-
chievous. I have known many fucceed well who
have been thus left to feparate, but veiy few that
were otherwife treated: nay 5 have known fome

extraordinary

LYMPHiEDUCTS. 209

extraordinary inftances of fuccefs -where the pa-
tient had the happinefs to have no one about them /
to interrupt the kind affiftance of nature.

CHAP. X.

OF THE LYMPHiEDUCTS.

• LYMPHiEDUCTS are fmall pellucid cylin-
drical tubes, which arife inviifyle from the ex-
tremities of the arteries throughout the whole bo-
dy, but more plentifully in glands than other parts,
and in greateft number from fuch glands as feparate
the mod vifcid fluids, as may be obferved in the liver
and teftes.. They cannot be difcerned in a natural
ftate to have more than one coat, and that exceed-
ing thin, having valves at fmall and uncertain dis-
tances, to prevent the regrefs of their fluid. They
have frequent communications like the veins, but
do not unite fo often ; the larger trunks are in many
places attended with fmall glands, through which
they run, and at the fame time fend communicant
branches over them, that they might be fecured
againft obftrudxions from difeafes in thofe glands.

• They all terminate in the vafa lactea, or in the large
veins.. • All that rife in the abdomen empty into the
veiiou lacteaefecundi generis and receptaculum chyli;
thofe in the cavity of the thorax into the dudtus
thoracicus and the fubclavian veins. , Their ufes are

to

2io LYMPHJEDUCTS.

to carry lymph to dilute the chyle, to make it in-
corporate more readily with the blood (but not to
make it flow the better in the lacteals, as appeart
fufficiently from their not entering into the minuteft
lacteals) and to carry off fo much lymph as is
neceffary to leave the blood in fit temper to flow
through the veins ; for it is always obferved that in
fuch perfons as have their blood too thin, the glo-
buli cohere and form molecule, or polypufes,
which I imagine may arife from the globuli of the
blood not rubbing often enough, and with fufflcient
force one againft another to difunite them as fall
as they cohere. Thefe polypufes are frequently
found in all the large veins, and in the right au-
ricle and ventricle of the heart, efpecially in fuch
bodies as die hydropic or of any chronic difeafes.
Authors have defcribed and painted thefe vef-
fels as they appear when injected with mercury j
in which cafe the coat of thefe veffels being exceed-
ing thin, it is notable any where between the valves
tu refift cLe mercury's attracting itfelf into globules:
and the fame appearance alfo happens when they
are vaftly diftended ; becaufe the valves hindering
a diftention where they are feated, the fpaces be-
tween them approach to a fpherical figure from the
equal premire of the fluid, according to the degree
of their diftention : but in a natural ftate, when
they are filled with lymph, or when they are mod-
erately injected with air or water, they appear as
cylindrical as the veins. Any of thefe veffels being

burft,

LYMPH^DUCTS. six

burft, they caufe a dropfy in the cavity into which
they open, which is oftener in the abdomen than the
thorax. This kind of dropfy is fometimes cured by
tapping, and I believe the reafon why it no oftener
fucceeds is, that it generally takes its rife from a dif-
eafed liver. Formerly in this operation only part of
the water was drawn ofTat a time, and the tap fome-
times left in the wound to draw off more, which
was exceeding painful, and fometimes brought on
a mortification ; and if they drew off much water
at one time the patient was in great pain, and gen-
erally fainted, which was thought to proceed from
the lofs of too much of the liquor at once. But
Dr. Mead, obfervingthatthefe fymptoms could not
proceed from the lofs of an extravafated fluid,
foon found the true caufe, which was the fudden
want of the preffure of the abdominal mufcles
againft the parts contained in the abdomen ; and
in the year 1705, being then phyfician to St.
Thomas's hofpital, ordered it to be tried there in
the following manner : He dire&ed the abdomen
to be prefled by the hands of affiftants while the
water was running out, and afterwards kept rolled
till the mufcles recovered force to do their office,
and fo took out all the water at once, without any
inconvenience, which has made this operation not
very painful, fometimes fuccefsful, and never dan-
gerous. I preferved one woman, by fixteen ope-
rations, from the fifty-lixth. year of her age to eigh-
ty ; another fix years by fixty-fix tappings : it

mur\

ai2 LYMPHATIC GLANDS.

mull be confefTed, that few cafes fucceed like thefe,
and very few recover.

I opened a woman, who died of a dropfy in
the liver, in which I found the gibbous part en-
tirely wafted, and the coat of the liver about a
quarter of an inch thick, which contained about
five gallons of a grofs yellowifh fluid, in which
were many hydatids about the fize of goofeberries,
and fome pieces of matter of as bright a red as ver-
milion. At about fourteen years of age me firft
began to feel pain in this part, which returned
monthly, but in time grew continual, her belly
conftantly increafmg till fhe died, which was in
the twenty-eighth year of her age, without ever
having had her menfes. All the other vifcera both
in the thorax and abdomen were perfectly found,
nor was there the leaft fign of the dropfy in any
of the limbs, or yellownefs in the fkin, which is
frequent in difeafes of the liver.

CHAP. XL

Of the Lymphatic Glands.

1 H E glands accompanying the lymphatics
are fituated in the three cavities, in the inter-
fticcs of the mufcles, where the lymphatics lie with
the large blood veffels, and in the four emunclo-
ries, viz. the arm-pits and groins. „ In the brain

is

LYMPHATIC GLANDS. 215

is feated the glandula pinealis, which I judge to
be of this fort, having often feen large lymphsedu&s
running into it from the plexus choroides ; and at
the bafis of the brain in the cella turcica is the glan-
dula pituitaria, into which enters a large lymphatic,
as I imagine, named infundibulum (vid, chap. Of
the brain.) In the neck are fituated a great many
of thefe, by the fides of the carotid arteries and in-
ternal jugular veins, and two, or a fort of double
one, upon the larynx, immediately below the thy-
roid cartilage, from which fituation they derive the
name of thyroidese ; and juft within the thorax is
feated another, called thymus. In very young chil-
dren the thymus is as large, or larger, than the thy-
roic glands ; but in men thefe glands are very large,
and the thymus very fmall, the former having in-
creafed in about a double proportion of any other
gland of this kind, and the latter having rather di-
minifhed than increafed ; but in brutes, fuch as
have fallen under my obfervation, it is juft the con-
trary. From which obfervations I am inclined to
conclude, that they both belong to the very fame
lymphatics, and that either of them increafmg as
much as both ought to do if both increafed, an-
fwers the fame end as if both did ; and that the
reafon why the thymus increafes rather than the
thyroid glands in brutes, is becaufe the fhape of
their thorax affords convenient room for it to lodge
in ; and that in men the thyroid glands increafe
fo much, bee JR there is no room in that part of

the

214 LYMPHATIC GLANDS.

the thorax where the thymus is feated for a large
gland to be lodged. In dogs, a porpoife, and fomc
other animals, I have feen the lymphatics in the
thymus, and between the thymus and ductus tho-
racicus, full of chyle, and fo in many other lym-
phatics near the vafa la&ea. Under the bafis of the
heart, and at the fides of the lungs, where the great
veffels enter, are many of thefe glands, from the fize
of a pea to that of a hazel-nut. In the abdomen,
upon the loins, near the kidneys, and by the fides of
the iliac veffels, are many of thefe glands, which are
called lumbales ; and there are fome at the hollow
fide of the liver named hepatic^ : the mefentery
alfo is full of glands of a like appearance ; but thefe
fecm to belong only to the lacteal veins, unlefs fome
of them, which are feated at the bafis of the me-
fentery, among the venas lacteae fecundi generis,
belong to the lymphatics that come from the liver,
where the hepatic lymphatics pafs in their way to
the receptacuium chyli. The glands which accom-
pany the blood veffels in the limbs are few, and
uinributed in no certain order ; except thofe in the
four emunctories, i. c. in the arm-pits and groins,
named axillares and inguinales.

Brutes have one large one in the thigh, com-
monly called the pope's-eye ; this is feated about
the great veffels in the thigh, where they pafs
through the triceps mufcle. From this fitua-
tion, and not from any thing ext^fc-dinary in this
gland, it is that wounds are there fo dangerous.

The

LYMPHATIC GLANDS. *ij

The lymphatic glands are faid by Nuck, and
others after him, to be compofed of veficles, a d
not of veffels like other glands ; and that thefe ve-*
ficles are repofitories of lymph : but from their
appearance in a natural ftate, which is very com-
pact and uniform, there feems to -me to be but little
reafon for fuch a conjecture. Some have thought
their ufe to be by contracting to accelerate the mo-
tion of the fluid. in the lymphatics ; but that does
not feem very probable, becaufe a mufcular coat
would have been the readieft means to produce that
effect; befides, thofe veffels feldom enter any of
them without detaching a branch over at the fame
time, perhaps to prevent obftructions. And if thefe
glands were endued with a contracting power, which
is only prefumed without any proof, it would ftill
be difficult to conceive how fuch a power, applied
at uncertain fpaces, mould not rather obftruct than
accelerate the motion of lymph in the lymphatics,
unlefs there were valves to prevent a reflux ; and
even then, if this were a convenient piece of me-
chanifm, it would be ftrange it fhould no where tKe
in the body be made ufe of.

Thefe lymphatic glands being difeafed, are apt
to obftruct and occafion the burfting of the lym-
phatics that pafs through them ; which, if in the
breaft, caufes an incurable hydrops pectoris ; if in
the abdomen, the true afcites, attended with a waft-
ing of the liirts, vvhich is never cured, but may be

relieved by tapping.

CHAP.

Hl6 COURSE OF THE

CHAP. XII.

Of the Course of the Aliment and Flu-
ids, ABSTRACTED FROM THE FOREGOING

Chapters.

. 1 HE aliment being received into the mouth, is
there mafticated, and impregnated with faliva,
which is preffed out of the falivary glands by
the motions of the jaw and the mufcles that move
it and the tongue. Then it defcends through the
pharynx into the flomach, where it is digefled by
the juices of the flomach (which are what is
thrown out of the glands of its inmofl coat, and
faliva out of the mouth) and a moderate warmth
and attrition. Then it is thrown through the py-
lorus or right orifice of the flomach into the duo-
denum, where it is mixed with bile from the gall-
bladder and liver, and the pancreatic juice from
the pancreatic gland. Thefe fluids ferve farther to
attenuate and dilute the digefled aliment, and prob-
ably to make the fluid part feparate better from
the fasces. After this - it is continually moved by
the periflaltic motion of the guts, and the com-
preflion of the diaphragm and abdominal mufcles,
by which forces the fluid parts are preffed into the
latleals, and the grofs parts through the guts to the
anus..

• The chyle, or thin and milky cart of the ali-
ment, being received into the lactears from all the

final!

ALIMENT and FLUIDS. 217

fmall guts, they carry it into the receptaculum chy-
li, and from thence the ductus thoracicus carries it
into the left fubclavian vein, where it mixes with
the blood, and pafTes with it to the heart..
, All the veins being emptied into two branches,
viz. the afcending and defcending cava, they empty
into the right auricle of the heart ; the right auri-
cle unloads into the right ventricle, which throws
the blood through the pulmonary artery into the
lungs ; from the lungs the blood is brought by the
pulmonary veins into the left auricle, and from
that into the left ventricle, by which it is thrown
into the aorta, and diftributed through the body.
From the extremities of the arteries arife the veins
and lymphatics ; the veins to collect the blood and
bring it back to the heart ; and the lymphatics to.
return the lymph, or thinner part of the blood, from
the arteries to the veins and the vafa lactea, where it
mixes with the chyle, and then pafTes with it into
the left fubclavian vein and to the heart.,
, All the fluids that pafs into the' ftomach and
guts being carried into the blood vefTels, the great-
eft part of them are feparated and carried off by
proper veiTeis, viz. urine from the kidneys, bile
from the liver, &c. and thefe juices carry along
with them whatever might ! ! -* injurious to th<
animal economy..

#

P CHAP,

si* DURA MATER.

CHAP. XIII.

Or the Dura Mater and Pia Mater*

DURA mater is a very compact, ftrong mem-
brane, lining the Infide of the fcull, firmly ad-
hering at its bafis, and but lightly at the upper
part, except at the futures.. It has three proceies ;
the firit, named falx, begins at the crifta galli,
and runs backwards under the futura fagittalis to
the cerebellum, dividing the cerebrum into two
hemifpheres. Its ufe is faid to be to fupport one
fide of the cerebrum from pre/Ting on the other
when the head is inclined to one fide. But I
think it is evident that this is not the ufe, becaufe
there would be more need of fuch a procefs from
one fide of the fcull to the other, than this way ;
and it woukl alfo be very neceflary that it fhould
run through the brain, to anfwer that end. The
principal ufe appears to me to be, to divide the brain
into fuch portions as are leaft liable to be moved
in the fcull, by any violent motions of the head,
which is better done this way than it would the
other ; and the under fide of the brain is kept fteady
by the inequalities of the bafis of the fcull, which
the brain is exactly fitted to. In brutes the falx
is always very fmall, therefore in thofe whofe
brains are of the larger fize, as oxen, fheep, horfes,
&c. the upper part of the fcull is made uneven,
exadfcly to fit the folds of the brain, which fecures

the

DURA MATER. 219

the upper parts of their brains from concuflions, in
the fame manner that the lower parts are fecured.
The fecond procefs runs from the lower and back
part of the former to the upper edge of each os
petrofum, and fuftains the pofterior lobes of the
cerebrum, that they might not comprefs the cere-
bellum. In fuch rapacious animals as I have dif-
fered, this procefs is bone. The third is very
fmall ; it runs from thelaft defcribed procefs down
towards the great foramen of the fcull, and poffeffes
the fmall fpace in the cerebellum, between the pro-
cerus vermiformis. Thefe procelfes of the dura
mater alfo ferve to keep the brain fteady.
* The dura mater has in it feveral finufes, which
are large veins to receive the blood from the leffer
veins of the brain : their number is uncertain, and
thofe that are conftant are not defcribed in the
fame order by writers.. The firft that prefents itfelf
is the longitudinalis fuperior, running from a blind
hole a little above the crifta galli all along the
upper edge of the falx. A tranfverfe fe&ion of
this vefTel is not circular, like other veflels, but a
triangle, whofe fides are arches of a circle ; the
upper fide convex outwards, and the two lower
convex inwards. The figure of this vefTel is pre-
ferred by fmall ligaments running acrofs in the in-
fide, that it might not become conical, or cylindri-
cal, like other veffels, from the equal preflure of
the contained blood, and thereby incommode the
upper edges of each hemifphere of the cerebrum,

V 2 On

220 DURA MATER.

On the lower edge of this procefs is generally an-
other very fmall one, called longitudinalis inferior ;
this runs into the rectus, and when wanting is
fuppiied by a vein ;*the rectus runs between the two
firfl proceffes of the dura mater, and unloads with
the finus longitudinalis luperior into the two later-
al finufes ; but for the moll part the longitudinal
\ius goes more directly into one of the lateral 1 fi-
fesj and the ftraight finus- into the other. There
is fometimes a fmall one in the third procefs, which
ties in the fame place with the former. From
the endings of the longitudinal and ftraight finufes,
begin the two lateral finufes, which, when they
come to the os pctrcfum, clip down and pafs through
the eighth foramina into the internal jugular veins.
There is another named circularis ; it runs round
the fore part only of the cella turcica ; the two
ends of this empty into four finufes, one on the
too of each os petrofum, which pafs into the finus
lateralis, and one at the under fides of the fame
bones, which pafs indifferently into both the late-
ral and cervical finufes ; thefe two laft finufes have
always communicant branches. The cervical fi-
nufes run from the bafis of the fcull through the
great foramen on both fides of the medulla fpi-
nalTs colli, and through the tranfverfe proceffes of
the cervical vertebra : the laft of thefe have many
times proper foramina running from the eighth
foramina to the bock part of the apophyfes of the
occipital bone. There are alfo two more of thefe

veffels,

PIA MATER, 221

vefTels, which run from the circular firms between
the os fphenoides and fore part of the os petro-
fum directly into the internal jugular veins.

, Pia mater is an exceeding fine membrane im-
mediately inverting the brain, even between its
lobes, hemifpheres, and folds. , It ferves to contain
the brain, and fupport its blood veffels, which run
here in great numbers, for the arteries to divide
into fmall branches upon, that the Wood may not
enter the brain too impetuoufly : and for the veins
to unite on, that they may enter the finufes in
fewer and larger branches. Between the dura
and pia mater, is defcribed, by feveral anatomifts,
a membrane called arachnoides, which may eafily
be fhewn at the back part of the cerebrum, upon
the cerebellum and back part of the medulla
fpinalis.

I have feen a large part of the dura mater, and
once part of the pia mater omfied.

CHAP.

222 CEREBRUM.

CH^P. XIV.

Of the Cerebrum, Cerebellum, Medulla
Oblongata, and Medulla Spinalis.

CeREKRUM is that part of the brain which
poffefles a.U the upper and fore part of the
cranium, being feparated from the cerebellum
by the fecond procefs of the dura mater. Its
upper fide is divided into two hemifpheres, and its
lower fide into four lobes, two anterior and two
pofterior, which latter are much the largeft. . At
the meeting of the four lobes appears the infundi-
bulum, which feems to be a lymphatic, running
from the ventricles of the brain into the glandula
pituitaria : this gland is feated in the cella turcica.
Immediately behind the infundibulum appear two
fmall bodies, named protuberantise duse albas pone
infundibulum. Between the two hemifpheres of
the cerebrum, lower than the circumvolutions,
appears a white body named corpus callofum.
Under the corpus callofum appear the two lateral
or fuperior ventricles, which are divided into right
and left by a very thin membrane, named feptum
lucidum, which is extended between the corpus
callofum and fornix. The fornix is a medul-
lary body beginning from the fore part of thefe
ventricles, with two fmall roots which foon unite*;
and running towards the back part, where they
divide into parts, called crura fornicis.- In the

ban's

\t

CE-REBELLUM. 223

ban's of thefe two ventricles are four prominences :
. The two anterior are called (from their inner tex-
ture) corpora ftriata ; the other two are named
thalami nervorum opticorum. Beyond thefe are
two more precedes, called nates ; and under them,
nearer the cerebellum, two called teftes. Above
the nates is fituated the glandula pinealis, famous
for being fuppofed, by Des Cartes, the feat of
the foul. And upon the thalami nervorum opti-
corum are a number of blood veffels, glands, and
lymphseducts, called plexus choroides. Under the
beginning of the fornix is a fmall hole, called fo-
ramen ad radices fornices, or iter ad mfundibulum ;
and under the middle of the fornix, one called fo-
ramen pofterius, which is covered with a valve
named membrana, or valvula major ; and the fpace
under the two anterior ventricles between the for-
amina and the cerebellum is the third ventricle.
« Cerebellum is fituated under the fecond procefs
of the dura mater.. By dividing this part of the
brain lengthways we difcover more plainly the
fourth ventricle, whofe extremity is called calamus
fcriptorius ; here alfo appear two medullary bod-
ies called pedunculi, which are the bafis of the
cerebellum. The medullary part in the cerebellum,
though it is inmoft, as in the cerebrum, yet is of a
different fhape, being branched out like a plant.
> The fubftance of the brain is diftinguifhed into
outer and inner : the former is called corticalis, ci-
nerea, or glandulola ; the latter medullaris, alba, or
nervca.. Medulla

224 MEDULLA OBLONGATA, &c.

♦ Medulla oblongata is a medullary continuation
of the under part of the cerebrum and cerebellum..
It firfl appears in two bodies from the anterior
part of the posterior lobes of the cerebrum, call-
ed crura medulke oblongata?. The union of thefe
crura between the cerebrum and cerebellum is
called ifthmus ; and immediately beyond this is
an eminence named procerTus annularis.
' Medulla fpinalis is a production of the medulla
oblongata through the great foramen of the fcull,
and through the channel of the fpine :. it enlarg-
es about the laft vertebra? of the back and firft of
the neck, where the large nerves are given off to
the arms : it again enlarges in the loins, where the
crural nerves begin ; and the lower end of it, with
thofe and other nerves, is called from its refem-
blance cauda equina. The coats of this part are
the fame with thofe of the brain ; but the mem-
brane here, which is analogous to the dura mater,
is thinner and more connected to the bones, and
the tunica arachnoides more confpicuous.

♦■ Wounds in the cerebrum, though very danger-
ous, are not mortal ; but in the cerebellum and
medulla oblongata caufe fudden death ; and in the
medulla fpinalis, lofs of fenfe in all the parts which
receive nerves from below the wound.. In perfons
that have died lethargic, I have always found the
brain full of water ; and in children, the brain is
very foft and moid. In a man, that died
of an :■; y, I found all the vefTels of the brain

NERVES. 225

immoderately diftended with blood, and the ventri-
cles and the fubftance of the brain full of lymph,
the pia mater very much thickened, and adhering
fo very loofely that the greateft part of it was
feparated without breaking.

I have twice feen in the cerebrum a fcirrhous
tumor as large as a pullet s egg ; and in another
body, impoflhumations which pofTeffed near two
thirds of the whole cerebrum. And in a perfon
that died with a gutta ferena, I found all the ven-
tricles of the brain full of lymph ; and the tha-
lami nervorum opticorum and the optic nerves, ere
they went out of the fcull, made flat with the pref-
fure. And in an old man I found the right optic
nerve wafted and black.

CHAP. XV.
Of the Nerves.

" rROM the medullary part of the cerebrum,
" cerebellum, and medulla fpinalis, a vaft num-
" ber of fmall medullary white fibres are fent
" out, which, at their firft egrefs, feem eafily to
" feparate, but as they pafs forward are fomewhat
" more, but ftill loofely connected, by the coat
" which they obtain from the pia mater, and at
" lait piercing the dura mater, are ftraitly braced
" by that membrane which covers them in their
" progrefs ; whence they become white, firm,

" ftrong

226 NERVES.

" ftrong cords, and fo, are well known by the
" name of nerves. To thefe coats an infinite num-
" ber of veflels, both arteries and veins, are dif.
*' tributed ; fo that after a nice lucky injection the
** whole cord is tinged with the colour of the in-
jected liquor: but when the fibrils are examined,
" even with the beft microfcope, they appear only
" like fo many fmall diftinct threads running pa-
" rallel, without any cavity obfervable in them,
" though fome incautious obfervers, miftaking the
u cut orifices of the arterious and venous veflels,
" juft now mentioned, for nervous tubes, have af-
w firmed their cavities to be vifible. The nerves,
" which if all joined hardly make a cord of an inch
" diameter, would feem, from their exerting them-
*' felves every where, to be diftributed to each, even
" the fmalleft part of the body. In their courfe
" to the places for which they are deftined, they
u generally run as ftraight as the part over which
" they are to pafs, and their own fafety from exter-
" nal injuries, will allow, fending off their branch-
" es at very acute angles, and confequently run-
" ning more parallel than the blood veflels. Their
u distribution is feldom different in the oppofite
'• fides of the fame fubjed, nor indeed in any
" two fubjeds is there confiderable variety found.
u -Frequently nerves which come out diftinc~t or
" feparate, afterwards conjoin into one fafciculus,
" under the fame common covering ; and though
*' the nervous fibrils probably do not communicate

« (the

NERVES. 227

" (the reafon of which opinion {hall immediately
" be given) yet becaufe the coats at the conjoined
"part are common, and thefe ftrong coats may
" have great effects on the foft pulpy nerves, it is
*' evident all fuch will have a confiderable fympa-
" thy with one another, whereof feveral exam-
" pies in practice fhall be inftanced when the par-
" ticular nerves are defcribed. In fome parts
" where there are fuch conjunctions, the bulk of
" the nerves feems much increafed, and thefe
" knotty oval bodies, called by Fallopius cor-
pora olivaria, and generally now named gang-
'• lions, are formed. The coats of thefe knots
" are ftronger, thicker, and more mufcular than
" the whole nerves which enter into them would
" feem to conftitute, while the nervous fibrils
" pafs through without any great alteration or
" change. I do not think any author has yet
" made a probable conjecture of the ufe or defign
" of thefe ganglions, whether they imagine them

• corcula expellentia, refervoirs, or elaboratories,
" neither can I give an account of their ufe the

• leaft fatisfactory to myfelf.

w From undeniable evident experiments, all an-
" atomifls are now convinced that to the nerves
" we owe all our fenfation and motion, of which
" they are the proper organs ; and the fenfations
" in the minuteft parts being very diftincl:, there-
** fore the inflruments of fuch fenfations muft have
** diitincl: origins and courfe to each part. Though

«« all

228 NERVES.

u all are agreed as to the effect, yet a hot difpute
" has arifen about the manner how it is produced,
" viz. whether fenfation and motion are occafioned
" by a vibration communicated to the nerves, which
" thefe gentlemen fuppofe entirely folid and tenfe,
" or by a liquid contained and moved in them.
" The laft of thefe opinions I rather incline to, for
" thefe reafons, becaufe the nerves proceeding from
" the brain bear a great analogy to the excretory
" ducts of other glands. Then they are far from
" being ftretched and tenfe in order to vibrate.
" And what brings the exiftence of a liquid in their
" cavities next to a demonstration is the experiment
" firft made by Bellini, and related by Bohn
"and Pitcairn, which I have often done with
" exact good fuccefs ; it is this : After opening the
" thorax of a living dog, catch hold of and comprefs
" the phrenic nerve, immediately the diaphragm
" ceafes to act ; remove the compreffing force, that
" mufcle again contracts ; gripe the nerve with one
" hand fome way above the diaphragm, that fep-
" turn is unactive ; then with the other hand ftrip
" down the nerve from the firft hand to the dia-
" phragm, this mufcle again contracts ; after once
" or twice having flopped the nerve thus down
" or exhaufted the liquid contained in it, the muf-
" cle no more acts, fqueeze as you will, till the
" firft hand is taken away or removed higher, and
" the nerve ftrippecl, i. c. the liquids in the fupe-
" rior part of the nerve have free accefs to the dia-

" phragm ,

NERVE S. 229

" phragm, or are forced down to it, when it again
" will move. Now if this liquid mould be granted
" us, I am afraid we fhall be ftill as much at a
" lofs to account for fenfation and motion as ever ;
" and therefore all I fhall afTume is what is found-
" ed on experiments, that thefe two actions do de-
" pend on the nerves ; that fenfations are pleafant
" as long as the nerves are only gently affected
" without any violence offered them ; but as foon
" as any force applied goes beyond this, and
" threatens a folution of union, it creates that
" uneafy fenfation, pain : the nerves, their fource
" or their coats being vitiated, either convulfion or
" palfy of the mufcles may enfue.
** "The nerves are diftinguifhed into two claffes,
" of the encephalon and medulla fpinalis ; of the
" firft there are generally ten pair reckoned, of
" the laft thirty.. I fhall defcribe the nerves in
" the fame order in which they are generally
" ranked, though it is not poffible to profecute the
" difTecTion of them after the fame manner ; but
" to fupply this, I fhall mention alfo the order
" wherein they may be all demonftrated on one
" fubje^t. When I afhgn the origin of any nerve
" from any particular part, I defire it may be un-
" derflood of that part of the furface of the me-
" dulla, where the nerve firft appears ; for by this
" method we fhall fhun any difpute with thofe au-
u thors who trace their rife too minutely, and per-
" haps be lefs liable to miflake or to deceive our

" readers.

230 NERVES.

" readers. Nor fhall I be over anxious about the
u terminations of the minima? fibrillse, fince it is
*' not poffible to trace them ad ultimos fines, nor
" do I think it very necelfary for explaining any
" phenomena, while very often in a multiplicity of
" words the whole defcription comes to be obfcure
" or unintelligible.

" Of the ten pair proceeding from the encepha-
<c Ion, the firft is the olfactory, which in brutes,
"juftly enough, has the name of procefTus ma-
u millares beflowed on them, being large and hol-
" low, and are indeed evidently the two anterior
*' ventricles of the brain produced ; which ftructure
u and the lymph conftantly found in them, induced
" the ancients to believe that they ferved as emunc-
<l tories to convey the fuperabundant mucus from
" the cold moift brain to the nofe ; but in man
" they are fmall, long, and without any cavity,
** rifing from that part of the brain where the ca-
<c rottd arteries are about to enter, and running un-
" der the anterior lobes of the brain become a little
•* larger, till they reach the os cribriforme, into
" the foramina of which the fmall filaments in-
44 finuate themfelves, as upon gently pulling thofe
u nerves, or after having cut them very near the
" bone, is evident, and are immediately fpread on
" the membrana narium. Their tender ftructure
il and fudden expanfion on fuch a large furface,
44 make it impoflible to trace them on the mem-
" brane of the noftrils, which has given fome handle

"to

.

NERVES. 231

7 to feveral authors to deny them the ftructure or
" ufe of nerves.

" The fecond are the optic, which arife Tingle
" from the thalami nervorum opticorum, and then
" uniting at the fore part of the cella turcica, they
" feem to be pretty much blended ; afterwards they
" divide, and running obliquely forwards, pafs out
" at their proper hole of the fphenoide bone, and
" enter the globe of the eye to be expanded into
u the membrana retina. From this conjuction of
" thefe nerves, authors generally endeavour to ac-
" count for our feeing objects fingle, whereas we
" have reafon to believe fifties, the chamseleon, &c.
" whofe optic nerves {imply crofs one another with-
u out any fuch union, do fee objects alfo fmgle,
" fmce they fo exactly ru(h on their prey ; where-
" as if thofe authors' aflertions were true, they
" would oftener catch at the fhadow than the fub-
" fiance. The blood veflels running through the
M middle of thefe nerves, and the ramifications of
" the retina are very obfervable, whence we may
"deduce the reaibn of Pic ard's experiment of
" fuch objects as fall on the entry of the optic nerve
M being loft to us ; and hence alfo an account may
M be given of an amaurofis or gutta ferena.

" The third pair of nerves firft appear at the
" anterior part of the proceflus annularis, and go-
u ing out at the foramen lacerum, are diftributed to
u the gl(^->e of the eye ; mufculus rectus Fallopii v
Kl attoiens, adducens, deprimen^ and obliquus mi-

** nor ;

232 NERVE S.

" nor ; therefore this pair has juftly got the name
" of motores oculi.

" The fourth pair, which are the fmalleft of
" any, derive their origins from the anterior lateral
" part of the proceflus annularis, and go out at the
" foramina lacera to be entirely fpent on the muf-
" culi trochleares, or obliqui majcres oculorum,
" to which mufcles chiefly the rotatory motion of
" the eyes in ogling, and the advance of the eyes
" forward in flaring and fury, is owing ; for
" which reafon anatomiils have called thefe nerves
" pathetici.

" The fifth pair arife from the fides of the an-
" nular procefs, and after piercing the dura mater
" divide into three branches ; the firft of which is
" the ophthalmic, which as it is about to enter
" the orbit by the foramen lacerum, fends off a
" fmall twig that afhfls in the formation of the
" intercoftal, and then the nerve is diftributed to
" the glandula lacrymalis, fat membranes, and pal-
" pebne of the eye, while it fends one confidcrable
" branch through the orbiter internus anterior hole
" to be loft in the membrana narium, and a fecond
" paffes the foramen and fupercilia to fupply the
" mufcles and teguments of the forehead. Hence
" we eafily difcover what part is affected in th.it
" painful difeafe the megrim, when the eye-ball
" and forhead are racked, and fuch a heat is felt
" within the nofe. Hence alio we may learn how
"'• the mufcles of refpiralion come to be ib much

" affeded

SERVES. 233

li afTe&ed on the application of any acrid irritating
" fubftance to the membrana narium, as to pro-
" duce that violent convulfive motion, fneezing.
" The fecond branch of the fifth pair, which may
" be called maxillaris fuperior, paries out through
" the foramen rotundum offis fphenoidis, and im-
" mediately gives nerves to the fat under the cro-»
"taphite mufcle, and to the palate, finus fphenoi-
" dalis, and noftrils. The remaining trunk inflnu-
" ating itfelf into the channel on the top of the
" antrum Highmorianum, to which cavity and to
" the teeth of the upper jaw it gives fmall twigs,
" at lafl comes out at the orbiter externus hole,
" and is fpent on the mufculus orbicularis palpebra-
" rum, nofe, and upper lip, where fome branches
" of the feventh pair feem to unite themfelves to
" the twigs of this. The third branch, or max-
" illaris inferior, goes out at the foramen ovale, or
" fourth hole of the wedge-like bonej and foon
" fplitting into a great many branches, is diftrib-
" uted to the mufculus crotaphites, mafleter, pte-
" rygoides, digaftricus, buccinator, mylohyoideus,
"' geniohyoideus, genio-glofiiis, and bafio-gloffus,
a glandula fublingualis, maxillaris inferior, and
" parotis, to the external ear, where it feems to join
" the portio dura to the fubftance of the tongue,
" in which it is pretty much confounded with the
" ninth pair : from the root of this laft branch the
" chorda tympani is reflected. The laft ramifi-
" cation of this branch which I fhall mention, is
Q^ " that

234 NERVE S.

" that which enters into the canal of the lower jaw
" furnifhes the teeth there, and comes out at the
" chin, on which and the lower' lip it is beftowed ;
" at this place it is again conjoined to the feventh
" pair. " From this fhort {ketch of the large fifth
" pair of nerves, and by obferving feveral phamom-
" ena which happen to thofe parts to which they
44 are distributed, we might have a much farther
*' confirmation of the general doctrine of nerves
u delivered, and fee, at leaft, the way pathed to a
" ratioiial account of thefe phenomena, for reafon-
" ing on which we mould not otherwife have the
44 leaft ground. We can, for example, from the
" chorda tympani and the nerves of the teeth, be-
" ing derived from the fame common trunk, Un-
" derftand how the found of any vibrating body
" held between our teeth is fenfible to us, when
" another cannot poffibly hear the leaft of it. By
44 the like rule we know why in a violent tooth-
" ache the mufcles of the face are fometimes con-
" vulfed ; nor fhall we be furprifed to hear one
44 plagued with the ache in his upper teeth, com-
" plain of a gnawing pain deep feated in the bones
44 of his face, or to fee his eye-lids much fwelled,
" or the tears trickling down in great abundance ;
44 whereas the lower teeth aching, the ear is pain-
" ed, and the faliva flows in great quantities. We
44 may have fome diftant views of fome foundation
44 in reafon for the cure of the tooth-ache, by ftrong
" compreffion of the chin, or by applying blifters

44 behind

NERVES. a 3 $

" behind the ears, or by burning behind or on the
" ear. Among a great many inftances of the good
rt effeft of the adual cautery in fuch a cafe, I fhall
M give one which feems to be remarkable t I. M.
" was feized with the tooth-ache, a convulfion of
" that whole fide of his face followed whenever
"the pain became acute, or he attempted to
" fpeak ; after he had undergone bleeding, purg-
" ing, falivation, fetons, &c. without any benefit,
u he was cured by applying a fmall cauterifing
" iron to the antihelix.

" The fixth pair of nerves arifing from the fore
4t part of the Corpora pyramidalia, after piercing
" through the dura mater, give off a branch,
" which, joined with the reflected twig of the oph-
" thalmic branch of the fifth pair, forms the origi-
" nal of the intercoftal, paffes through the fora-
*' men lacerum to be fpent entirely on the mu£*
" cuius abductor oculi : fuppofing this nerve to
" fupply ever fo little lefs than a due proportion
" of liquidum nervofum, an involuntary ftrabif*
" mus will be occafioned.

" Though the fifth and fixth pair of nerves
" form entirely the beginning of the intercoftal be-
f fore it goes out of the fculi, yet becaufe feveral
" other nerves contribute towards the formation of
" its trunk before k fends off any branches, I (hall
" fuperfede the defcriptioa of it till the original
*' nerve* are fpoke to.

0^2 '<The

136 NERVE S.

"The feventh pair appears coming out from
" the fide of the root of the annular procefs, and
"entering the meatus auditorius internus, and
" immediately dividing, one part foon lofes its
" firm coats, and is expanded on the inmoft ca-
" mera of the ear, while the other pairing through
" the aquaedu&us Fallopii comes out of the fcull
" involved in all its coats between the ftyloide and
" maftoide procefles ; whence we fee the reafon of
"the firft being named portio mollis, and the
" other dura : this laft after its exit fcpplies the
"mufculi obliqui capitis ftylohyoidei, ftyloglofii,
" and ftylopharyngsei, and platyfma myoides, on
" which, and to the fkin of the neck, a great num-
" ber of its fmall filaments run, which are fome-
" times cut in opening the jugular vein, whence
"pain at firft, and a little numbnefs afterward.
" The fuperior branches of it fupply the parotid
" gland, external ear, and whole fide of the face
" as far forwards as the chin It is faid to com-
" municate thrice with the fifth pair, and twice
" with the fecond vertebra. Whether may not we
" hence fee fome reafon why the head is fo foon
" moved by the impreflion of found on our ear ?
" The eighth pair of nerves derive their origin
" from the fide of the bafis of the corpora olivaria,
" where their loofe filamentous texture is very con-
" fpicuous ; then running to the hole common to
" the oiTa temporum and occipitis, they are there
"joined by the accerTorius Williiii, which has its

" beginning

NERVES. 237

u beginning from the two or three fuperior nerves
"of the medulla fpinalis, and mounts upwards
" thither, to pafs out with the eighth pair, at that
" common foramen juft now mentioned : very
u foon after they, wrapped up in the fame coat,
V have got out of the cranium, the accefforius fep-
" arates from its companion, and after pafTmg
" through the middle of the mufculus maftoideus,
" is loft in the mufculus trapezius and rhomboides
" fcapulse ; while the large trunk, which, from the
" great number of branches it fends off, obtains
" the name of vagus, runs ftraight down the neck,
" near the carotid artery, in its courfe giving feve-
" ral branches to the larynx : when entered the
<c thorax, it fplits into two ; the anterior ferves the
" pericardium, fends branches to join with thofe
" of the intercoftal that go to the heart, and then
" on the right fide turns round the fubclavian, and
" on the left round the ductus arteriofus, to mount
" again upwards at the fide of the cefophagus to
" be loft in the larynx. This recurrent branch it
" is that we are earneftly cautioned to avoid in
" bronchotomy, though by reafon of its deep fitu-
" ation we are in no hazard of it. If both thefe
" nerves w T ere cut, it is probable the voice would
" not be entirely loft as long as the fuperior branch-
w es ftill fupply the larynx. The pofterior branch
" of the eighth pair goes along with the cefophagus,
** and fupplies the lungs, the gula, and ftomach
" very plentifully ; and as all the nerves beftowed

" on

238 NERVES.

w on this vifcus enter at the fuperior orifice of it,
" the fenfation here mud be very acute ; whence
"Helmont imagined the mouth of the ftomach
" to be the feat of the foul. What remains of
"this par vagum is adjoined to the intercoftal im-
ic mediate below the diaphragm.

" The ninth pair appear firft at the inferior
44 part of the corpora pyramidalia, and march out
" at their proper holes of the occipitis, and after
" fending off fome nerves to the glandula thyroi-
*' dea, and mufculi ftemo-hyoidei, and fterno-
" thyroidei, are loft in the fubftance of the tongue,
" Authors have difputed whether this ninth or
" the fifth is the guftatory nerve ; the old opinion
u in favour of the ninth is to me moft probable,
" becaufe the fifth is no where elfe employed as
" an organ of fenfation, hecaufe the ninth feems to
* c penetrate the fubftance of the tongue more,
" while the fifth is fpent on the mufcles.

" The tenth pair comes out from the beginning
" of the medulla fpinalis, betwixt the os occipitis
* and firft vertebra colli, and is all, except what
" goes to the ganglion of the intercoftal, fpent on
*' the mufculi obliqui, and extenfores capitis.

" The only nerves proceeding from the ence^
" phalon not defcribed, are the reflected branches
" of the fifth and fixth, which indeed are fo fmall
" and pappy, and hid by the carotid artery as they go
" out with it in its crooked canal, as not to be eafily
** traced ; but whenever they have efcaped from the

«os

NERVES. 239

• os petrofum, they are joined by branches from
"the eighth, ninth, tenth, and firft and fecond
" fpinal, and the largeft ganglion of the body is
" formed, from which the nerve named now in*
" tercoftal, goes out to defcend down the neck
" with the carotid, fupplying in its courfe the muf-
" culi flexores of the head and neck, and commu-
" nicating with the cervical nerves. As the inter-
" coftal is about to enter the thorax, it again forms
" a ganglion, from which the nerves to the trachea
" arteria and the heart are fupplied, which join with
" the branches of the eighth, and pafs between the
" two large arteries and auricles to the fubftance
" of that mufcle. Now let any one confider the
" egrefs of the intercoftal, and clofe courfe of it
" and the eighth with the carotid artery, and this
" manner of entry of the cardiac nerves, furely
" the alternate conftriction and relaxation of the
" heart will appear necefTarily depending on the
" difpofition of thefe organs of motion, the nerves.
" The intercoftal after this runs down on the fide
" of the vertebrae thoracis, having additional nerves
" conftantly fent to it from between thefe verte-
" bra, till it pafs through its own proper hole of
" the diaphragm ; whence it again forms another
"ganglion clofe by the glandulae renales, into
" which the eighth pair enter. From fuch a knot
" on each fide, the nerves of the guts, liver, fpleen,
"pancreas, and kidneys are derived; nay, the ex-
" tremity of this nerve is fent down to the pelvis

to

«4o NERVE S.

" to fupply the parts there. Hence the great fym-
" pathy of thefe parts may be eailly deduced, and
" a reafon may be given of the violent vomiting
" that commonly attends a nephritis, and of the
" belching, cholic, and ftomach-aches, which often
" enfue on the obftructions of the menftrua.

" Before I proceed to the fpinal nerves, I
<c fhall fet down the order in which thefe nerves
" already defcribed, are to be dkTected, in order
" to demonftrate them all in one fubje £t, but to
" them muft affume the three firft cervical nerves,
*' the reafon of which will be evident afterwards.

" Portio dura feptimi, frontalis quinti, facia-
" lis quinti, mentalis quinti, fpinalis fecundus,
" fpinalis primus, olfactorius, ophthalmicus quin-
" ti, motorius oculi, patheticus fextus, opticus,
" maxillaris inferior quinti, maxillaris fuperior
<c quinti, accefTorius Willifri, nonus, decimus, oc-
<c tavus intercoftalis, portio mollis feptimi.
• " The thirty pair of nerves proceeding from
" the medulla fpinalis are generally divided into
*' four fpecies ; of the neck feven, of the back
" twelve, of the loins five, and of the os facrum
" fix. , Now as the medulla fpinalis has none of
" thefe inequalities fo obfervable on the medulla
" oblongata encephali, the rife of the nerves is not
" fo accurately defcribed, being only determined by
" the bone through which they pafs.

" The firft cervical goes out between the firft
18 and fecond vertebra, and, after fendingoffbranches

« that

NERVES. £41

w that communicate with the tenth and fecond
** vertebrale, is fpent on the mufculus flexus colli,
" fplenius, complexus, and teguments of the occi-
" put.

" The fecond cervical communicates with the
" ninth, and with the firft and third of the neck,
•f and then is diftributed to the teguments of the
" neck and fide of the head, and to the glandula
"parotis and external ear, where it joins with the
" portio dura.

" The third of the neck paries out between the
" third and fourth vertebra, foon communicating
" with the fecond, and fending down a large
'* branch, which being joined by another from
" the fourth forms the phrenic nerve that runs
u along the pericardium to be loft in the dia-
" phragm, In this courfe the right phrenic is o-
" bliged to make a fmall turn round that part of the
" pericardium which covers the apex of the heart.
" Hence it is that fuch as have ftrong palpita^
** tions of the heart feel a pungent acute pain im-
" mediately above the right orifice of the ftomach.
" The other branches of this third cervical are
*' diftributed to the mufculus trapezius and del-
" toides, and to the teguments on the top of the
<'fhoulder; which, with the defcription of the
" eighth pair, leads us evidently to the reafons of
< c the divine Hippocrates's obfervation, that an
" inflammation of the liver is generally attend-
" ed with a hiccough, and a fuppuration of that

" vifcusj

24 2 NERVES.

44 vifcus, with a violent pain on the top of the
" fhoulder. However, we are not hence to con-
" elude fo generally, as I have obferved phyfician*
44 frequently do, that if the hypochondria are ef-
" fe&ed, and this pain of the fhoulder is felt, there-
44 fore the liver is fuppurated ; for any other caufe
" ftimulating or ftretching the nerves, fuch as in-
" flammation, wounds, fcirrhous or iteatomatous
** tumors, &c. may produce the fame effect.

44 The fourth cervical, after fending off that
44 branch which joins with the third to form the
"phrenic, runs ftraight to the axilla, where it
44 meets with the fifth, fixth, and feventh cervicals,
" and firft dorfal that efcape in the interflices of the
44 mufculi fcaleni ; and all of them are fo often
" conjoined and blended, after they have given off
44 nerves to the mufcles of the neck, fcapula, arm,
44 and thorax, and to the teguments, that when the
44 feveral ramifications go off in the axilla to the
44 different par:s of the fupdrior extremity, it is im-
44 poffible to determine which of them the branches
44 belong to. The confiderable branches into which
44 they are divided, are fix ; thefe I fhall prefume to
44 give proper diftinguifhing names to, by which the
44 defcription will be lefs confufed, and the young
44 anatomift's "memory better affifted to retain what
44 is fo difficult to reprefent in words.

44 i. Cutaneus runs down the fore part of the
44 arm, and ferves the teguments, as far as the palm
44 of the hand and fingers.

44 2. Mufculo-

NERVES. 243

• 2. Mufculo-cutaneus, or perforans caflerii,
u paffes through the mufeulus coracobrachialis, and
" after fupplying the biceps and brachials interims
M is fpent on the teguments of the back of the GU-
I' bitus and hand.

" 3. Mufcularis, that runs down the fore part
" of the arm to be loft in the mufculi flexores carpi,
" digitorum, &c.

" 4. Ulnaris, which fupplies the extenfores
" cubiti, and teguments of the elbow, and then
M palling through the finuofity at the back of the
M external condyle of the humerus, runs along the
" ulna, where it gives twigs to the teguments and
*' neighbouring mufcles ; at length is loft in the
u back of the hand, mufculi interofTei, and lumbri-
" cales in the little finger, and fide of the ring
" finger next to this. The courfe of this nerve is
il fufficiently felt when we lean on our elbow, by

* the infenfibility and prickling pain in the parts
" to which it is diftributed.

" 5. Radialis goes down the fore part of the
" arm, near the radius, beftowing branches in its
" progrefs on the circumjacent mufcles, and at the
" ligamentum annulare carpi fplitting, is fent to
" the thumb, fore finger, middle finger, and half
♦' the ring finger, and to the back of the hand.

" 6. Articularis runs almoft round the top of
"the os humeri, and ferves the mufculi exten-

* fores cubiti, retrattcres, and elevatores humeri.

"By

244 NERVES.

" By a ftrong and continued preflure on thefe
" nerves, by crutches or any fuch hard fubftance,
" a palfy and atrophy of the arm may be occa-
" fioned.

" The twelve dorfal nerves all communicate
" with one another : as foon as they make their
" way out betwixt the vertebra, each of them
"gives a poilerior branch to the mufculi ere&ores
" trunci corporis ; the firft, after having fent off
" the brachial nerve, already defcribed, is, after the
" fame manner with the fucceeding eight, be-
" flowed on the pleura and intercoftal mufcles ; the
" tenth and eleventh are moft of them fent to the
" abdominal mufcles ; the twelfth communicates
" with the firft lumbar, and is beftowed on the
" mufculus quadratus lumbalis and iliacus internus.
" The fifth lumbar alfo communicates and gives
" pofterior branches j the firft fends feveral branches
" to the abdominal mufcles, and pfoas, and iliacus,
" while others go from it to the teguments and
" mufcles on the fuperior and anterior part of the
" thigh, and the main trunk of it is loft in the
" crural. The fecond paffes through the pfoas
" mufcie, and is diftributed much as the former.
" The third is loft in the mufculus pe£tineus.
" Branches proceeding from the firft, fecond, and
" third, make up one trunk, which runs along the
" anterior part of the pelvis, and flipping through a
" fmall finuofity in the anterior part of the foramen
iC magnum offis ifchii, is fpent in the mufculus

" triceps.

NERVES. 245

" triceps. This nerve is commonly known by the
"name of obturator, or pofterior crural nerve.
" By the union of branches from the firft, fecond,
"third, and fourth lumbar nerves, the anteriof
" crural nerve is formed, which running along the
"mufculus pfoas, efcapes with the large blood
" vefTels out of the abdomen below the tendinous
" arcade of its mufcles, and is diftributed to the
" mufcles and teguments on the fore part of the
" thigh : One branch of this crural nerve accom-
" panies the vena faphena as far as the ancle. Now
" let us imagine the fituation of the kidney upon,
" and the courfe of the ureter over thefe nerves,
" and we mall not be furprifed, that in a nephritis
"the trunk of the body cannot be raifed eredt
" without great pain ; that the thigh lofes of its
" fenfibility, and that it is drawn forwards. The '
"remainder of the fourth and the fifth lumbar
"nerves join with the firft, fecond, and third that
" proceed from the os facrum : thefe five, when
" united, conftitute the largeft nerve of the body,
" fo well known by the name of the fciatic, or
" ifchiatic nerve, which feems to be bigger, in
" proportion to the part for the ufe of which it is,
" than the nerves of any other part are ; the de-
" fign of which may be to afford fufficient ftrength
" to the mufcles of the lower extremity, for ex-
" erting a force fuperior to what is required in any
" other part of the body. When this nerve is any
" way obftructed, we fee how unable we are to

" fupport

2 4 6 N £ R V E S.

" fupport ourfelves, or to walk. Tke fciatic nerve
" then goes out at the large hollow behind the
"great tubercle of the os ifchium, and parting
" over the quadrigemini mufcles, runs down the
" pofterior part of the thigh, giving off, every
" where as it goes, nerves to the teguments and
" mufcles of the thigh and leg. At the ham it
" fplits i nto two ; the fmaller mounts Over the fi-
" bula, and ferving the mufculi peronei, fiexores
" pedis, and extenfores digitorum, is continued to
" the toes along the broad of the foot, while the
" larger trunk finks under the mufculi gemelli,
" and then divides ; one is fpent in the mufcles
"at the back of the leg and teguments, while
" the other is continued by the inner ancle to the
" foot, and then fubdivides ; one branch is diftrib-
" uted after the fame manner as the ulnaris, and
" the other as the radialis in the hand.

" The other nerves that come out of the os fa-
" crum, are fent to the organs of generation, muf-
" culi levatores ani, and obturatores.

" Thefe nerves of the medulla fpinaiis may all
" be diffe&ed and demonftrated in the fame order
" in which they are defcribed." For this accurate
defcription of the nerves I am obliged to Mr.
Monro.

The nerves feem, when examined with a mi-
crofcope,to be bundles of ftraight fibres not commu-
nicating with one another: and I am inclined to
think, that every the minuteft nerve terminating

m

NERVES. 247

in any part, is a diftincl: cord from its origin in the
brain or fpinal marrow ; or elfe I do not fee how
they could produce diftincl: fenfations in every part i
and the diftinct points of fenfation throughout the
body are fo very numerous, that the whole body of
nerves (which taken together would not make a
cord of an inch diameter) muft be divided into filch
a number, to afford one for every part that has a
diftincT: fenfation, that furely fuch a nerve would
be too fmall to be feen by the beft micrcfcope.
They all pafs in as direct: courfes to the places they
ferve, as is poflible, never feparating nor joining
with one another but at very acute angles, unlefs
where they Unite in thofe knots which are called
ganglions, the ufe of which I do not pretend to
know ; they make what appears to be a communi-
cation of molt of the nerves on the fame fide, but
never join nerves on oppofite fides.

That the nerves are inftruments of fenfation,
is clearly proved from experiments, but how they
convey thofe fenfations to the brain, is matter of
difpute. The moft general opinion is ; that they
are tubes to contain animal fpirits, by whofe mo-
tions thefe fenfations are conveyed : and diligent
inquiry has been made to difcover their cavities,
but hitherto in vain ; and if each nerve is diftincl:
from its origin, as I have endeavoured to ihew, and
too fmall to be the object of the beft microfcope, I
do not fee how fuch cavities are like to be difcov-

ercci.

s 4 8 NERVES.

ered. Neverthelefs nerves may be tubes, and
pofhbly a fluid, whofe cohefion is very little, aud
whofe parts, no finer than light, may move freely
in them. Thofe who deny animal fpirits in the
nerves, fuppofe that the fenfation is conveyed by a
vibration. To which it is objected, that they are
flack, moift, and furrounded with foft parts, and
are therefore unfit for vibrations, as indeed they
are for fuch as are made on the firings of a mufi-
cal inftrument ; but the minuteft vibrations, fuch
as they cannot be without, may, for aught we
know, be as fufficient for this end, as the impulfe
of light upon the retina is for the fenfe of feeing.
So that perhaps fenfations may be conveyed ei-
ther, or both ways. However, it being ufually
taken for granted, that it muft be one of thefe
ways at leaft, the advocates for each have rather
endeavoured to fupport their opinions by argu-
ments againft the probability of the other, than by
reafons offered for their own.

TAB.

:.■

( H9 )

TAB. XXI.

1 Larynx.

2 The internal jugular vein.

3 The fubclavian vein.

4 Cava defcendens.

5 The right auricle of the heart.

6 The right ventricle.

7 Part of the left ventricle.

8 Aorta afcendens.

9 Arteria pulmonalis.

io The right lobe of the lungs, part of which is
cut off to fhew the great blood veffels.

1 1 The left lobe of the lungs.

12 The diaphragm.

13 The liver.

14 The ligamentum rotundum.

15 The gall-bladder.

16 The ftomach, preffed by the liver towards the

left fide.

17 The fmall guts.

18 The fpleen.

R TAB.

( 2 5° )

TAB. XXII.

X The under fide of the liver.

2 Ligamentum rotundum.

3 The gall-bladder.

4 The pancreas.

5 The fpleen.

6 The kidney.

j Aorta afcendens.

8 Vena cava afcendens.

9 The emulgent vein.

io A probe under the fpermatic veffels and the
arteria mefenterica inferior, and over the
ureters.

1 1 The ureter.

1 2 The iliac veffels.

13 The rectum inteftinum,

14 The bladder of urine,

TAB.

TAB .XXII.

P 2 5

TAB. Will.

I 2 5* )

TAB. XXIII.

1 Part of the inteftinum jejunum.

2 The valvulse conniventcs, as they appear in a,

dried preparation.

3 The venge lacteae arifing from the gut, and paffc

ing through part of the mefentery.

4 Part of the defcending aorta.

5 Arteria coeliaca.

<6 Mefenterica fuperjor.

7 Emulgentes.

8 Spermaticae.

9 Some of the branches of the mefenterica infe*

rior that are beftowed upon the guts,

R % TAB.

( 2 5 2 )

TAB. XXIV.

i Extreme branches of the vena porta, as they
arife from the guts.

2 All the branches of the vena porta, united be-

fore it enters the liver.

3 The branches of the vena porta, as they are

diftributed in the liver.

TAB.

TA13.XXIV

P. 2,52,.

TAB XXV

( 253 )

TAB. XXV.

i Branches of the vena cava in the liver*

2 Part of the vena cava afcendens.

3 Part of the right auricle.

4 Ciftis hepatica.

5 Ductus fifticus.

6 Ductus hepaticus.

7 Dudtus pancreaticus.

8 The entrance of the dudus communis into the

duodenum,

TAB,

( *54 )

TAB. XXVL

1 The left fubclavian vein.

2 The internal jugular.

3 Part of the vena azygos.

4 Part of the defcending aorta.

5 The fubclavian artery.

6 Some of the lacteals entering the receptaculum

chyli.

7 Some lymphatics entering the receptaculum

chyli.
S, 9 The Ductus thoracicus.
to The entrance of the thoracic duel: into the fub ?
clavian vein.

TAB.

tab .xxvi

p.

I'Aivxwi:

/

( *55 )

TAB, XXVII.

1 The humeral artery.

2 Cubitalis fuperior.

3 Cubitalis inferior, which ends in the hand and

the fingers, and communicates with the
cubitalis fuperior, under the mufcles of the
thumb.

4 The place where the cubitalis media is giv-

en off.

5 The fuperior cubital nerve.

6 The inferior cubital nerve, which paffes un-

der the inner extuberance of the os hu-
meri ; both thefe nerves give off branches
as they pafs, and end in the thumb and
fingers,

TAB.

( 256 )

TAB. XXVIII.

i Part of the biceps flexor cubiti.

i The fafcia tendinofa from that mufcle, which

is liable to be pricked in bleeding in the ba-

filic vein.

3 The humeral artery, on each fide of which is

a large vein.

4 Vena cephalica.

5 Mediana.

6 Bafilica.

7 A tumor formed in the centre of the cubital

nerve, a little above the bend of the arm ; it
was of the ciftic kind, but contained a trans-
parent jelly ; the filaments of the nerve were
divided and ran over its furface. This tumor
occafioned a great numbnefs in all the parts
that nerve leads to, and excefTive pain upon
the leaft touch or motion. This operation
was done but a few weeks fince, the pain is
entirely ceafed, the numbnefs a little increafed,
and the limb, as yet, not wafted.

TAB.

TAB.XXVUI.

P.BSm

L/\B. A A I A

'

( 257 )

TAB. XXIX.

i The medulla fpinalis, from whence arife the
nerves that pafs out between the vertebrae.

2 The brachial nerves.

3 The beginning of the cauda equina,

4 The anterior crural nerves.

5 The pofterior crural nerves.

6 The defcending intercoftal.

7 Nerves of the neck.

8 The brachial nerves.

o A ganglion in the defcending intercoftal nerve,
io Branches from the intercoftal nerve to the
vifcera.

1 1 A probe paffed under fome of the intercoftal

nerves that pafs out between the ribs.

1 2 The anterior crural nerves.

TAB.

{ *s* )

T A p. XXX.

x The animalculse in femine mafculino, as they
appeared in a microfcope, in a fpace as fmalj
as a pin's head.

S The circulation of the blood in a fifiVs tail, as
it appeared in a microfcope.

3 An artery, as it is fpread in a membrane,

4 A vein, as it is fpread in a membrane,

THE

TAli. AAA.

T. 2, St

*-

THE

ANATOMY

Of THE

HUMAN BODY.
BOOK IV.

CHAP. I.

Of the Urinary and Genital Parts of
Men, together with the Glandulje
Renales.

•THE urinary parts are the kidneys with their
veffels and bladder of urine. .

• The kidneys of men are like thofe of hogs ;
the two weigh about twelve ounces ; they are
feated towards the upper part of the loins upon
the two laft ribs ; the right under the liver, and a
little lower than the other, and the left under the
fpleen.j Their ufe is to feparate the urine from the
blood, which is brought thither for that purpofe

by

2 6o URINARY and GENITAL

by the emulgent arteries ; and what remains from
the fecretion, is returned by the emulgent veins,
while the urine fecreted is carried off through the
ureters to the bladder. I have, in three different
fubjects, taken ftones out of the loins, which had
made their ways from the kidneys through the muf-
cles to the common integuments, where, upon open-
ing the fkin only, the ftones appeared with a quan-
tity of matter and urine. We have heard of ope-
rators who have cut for the ftone in the kidneys ;
but I will venture to affirm, that thofe cafes were no
other than thefe, though unfairly related.

• The ureters are tubes about the bignefs of goofe-
quills, and about a foot long ; they arife from the
hollow fide of the kidneys, and end in the bladder
near its neck, running obliquely for the fpace of
an inch between its coats ; which manner of enter-
ing is to them as valves.. The beginning of the
ureters in the kidneys are the tubuli urinarii, which
joining form the pelvis in each kidney. Between
the tubuli urinarii, authors have remarked fmali
papillae ; and the parts which are diftinguifhed by
a clearer colour they call glandulse.

• The bladder of urine is feated in a duplicature
of the peritonaeum in the lower part of the pelvis
of the abdomen ; its mape is orbicular, and its
coats are the fame with thofe of the gats and other
hollow mufcles already defcribed ;• viz. an external
membranous, a middle mufcular, which is the muf-
culus detrufor urinse, and an inner membranous

coat.

PARTS of MEN. 261

coat, exceeding fenfible, as is fully fhewn in the
cafes of the ftone and gravel. The uie of this
nice fenfe is to make it capable of that uneafmefs
which excites animals to exclude their water, when
the bladder is extended. This fenfe is fo delicate,
that no fluid but natural urine can be long endured,
even pale urine, or urine with matter in it, in a
degree excite the fymptoms of the ftone, and force
the perfon to void the urine. Sometimes much
matter from the kidneys will excite vehement fymp-
toms ; and this being found in the urine, and the
pain being obferved in the bladder only, the kidneys-
having little fenfe cf pain, it is ufually accounted
for from ulcers in the bladder, which I have never
found one inftance of in all the numbers that I have
opened in this cafe. Indeed the bladder is fometimes
ulcerated, but that deftroying part of the inner coat,
the others ftretch and ulcerate till the urine burfts
through into the cellular membrane of the perito-
naeum, and caufe a moft miferable death. This cafe
is very rare in men, and much more fo in women.
I have feen cancerous ulcers open the bladder into
the uterus, but thefe, I think, have begun in the
uterus. All thefe cafes have fymptoms like the
ftone ; and not thefe only, but all difeafes of the
uterus which difturb the bladder, and even impof-
tumations or tumors that prefs upon the bladder,
all give the fame fymptoms with the ftone ; except
that of a needlefs difpofition to ftool at the time of
making water. Some anatomifts, not thinking how

loop

i6z URINARY and GENITAL

foon fluids taken into the ftomach, arid not retained
there by being mixed with folids, may pafs into the
blood, as the effects from drinking ftrong liquors or
laudanum, or drinking without eating when we arc
hot, fufficiently fhew ; and alfo not considering the
fhortnefs of the courfe from the ftomach to the kid-
neys this way, together with the fize of the emul-
gent arteries, and the velocity of the blood in them
have imagined and affirmed, that there muft be fome
more immediate courfe from the ftomach or guts to
the bladder ; and not ccniidering either how fuch a
courfe would have interrupted one great end in the
animal economy, or that vcffels fit to fill the blad-
der falter than the ureters, muft have been too large
to be concealed : nor, which proves it beyond con-
tradiction, that the bladder is empty when the kid-
neys ceafe to do their office ; which is frequently
taken for a fuppreffion of urine in the bladder.
If in this laft cafe, upon making a preflure on the
region of' the bladder, the patient does not feel great
pain, it is fcarce worth while to pafs a catheter to
fearch for urine. In iuppreffions of urine,,wheth-
er merely inflammatory, or from the gout, or
from an inflamed ftriclure in the urethra, I have
found nothing fo effectual as bleeding and purging.
In a fanguine large man, where the penis was too
much inflamed to fuflfer the catheter to pafs, I took
away three times twenty-four ounces of blood, and
gave a purging clyfter, and two ftrong purges, all
within the fpace of twenty hours, which faved

the

PARTS of MEN. 263

die patient, and delivered him from exceffive tor-
ment. Such practice may feem very fevere, but
in this cafe no time is to be fofl ; if the urine can
be drawn off, the method of cure is ftill the fame,
but to be pra&ifed in a gentler manner.

Glandule renales are two glands feated imme-
diately above the kidneys, of no certain figure,
nor do we know their ufe ; but always paint and
delcribe them with the urinary parts, beeaufe of
their fituation : in a very young foetus they are
larger than the kidneys, and in an adult but a little
larger than in a foetus. They receive a great many
fmall arteries, and return each of them one or two
veins. In their infide is a fmall finus, tinctured
with a footy-coloured liquor.
' The teftes are feated in the fcrotum ; their of-
fice is to feparate the feed from the blood ; they
are faid to have four coats, two common, and
two proper. . The common are the outer hVin and
a loofe membrane immediately underneath, called
dartos. The firft of the proper is the proceflus va-
ginalis ; it is continued from the peritonaeum to the
tefticle, which it enclofes with all its veffels, but is
divided by a feptum, or an adhefion immediately
above the tefticle, fo that no liquor can pais ou: of
that part of this membrane, which inclofes the fper-
matic veffels, into that which inclofes the tefticle.
Large quantities of water are fometimes found in
either or both of thefe cavities, which difeafe is
eafily remedied by a puncture with a lancet ; but

rarely

264 URINARY and GENITAL

rarely cured without opening the cavity where the
water is contained, as in finuous ulcers. This I
have done, and feen done feveral times, but never
thought the cure worth the trouble and pain the
patient underwent. The true hernia aquofa is from
the abdomen, which either extends the peritonaeum
into the fcrotum, or breaks it, and then forms a
new membrane which thickens as it extends, as in
aneurifms and atheromatous tumors. This may
be decided by an injection, which will Ihew by the
arteries that nourifh it, whether it is a production
from the peritonaeum, or a new membranous bag
formed in the fcrotum : however, the dropfy in
this cift, for filch it properly is, rarely admits of
more than a palliative cure by puncture or tapping,
like the dropfy of the abdomen, and this with fome
difficulty, becaufe the omentum ufually, and fome-
times the gut, defcends with it. The other proper
coat is the albuginea, which is very ftrong, imme-
diately inclofing the tefticles. The tefticles of a rat
may be unravelled into diftincl: veffels ; and the tex-
ture of the tefticles of other animals appear to be
the lame, hut their veffels are too tender, or co-
here too much to be lb feparated. The tefticles
receive each one artery from the aorta, a little be-
low the emulgcnts, which, unlike all other arte-
ries, arife fmall, and dilate in their progrefs, that
the velocity of the blood may be fufhciently abated ,
for the fecretion of fo vifcid a fluid as the feed. The
righi: tefticle returns its vein into the cava, and the

left

PARTS of MEN. 26s

left into the emulgent vein on the fame fide, both
becaufe it is the readied courfe, and becaufe, as au-
thors fay, this fpermatic vein would have been ob-
ftru&ed by the pulfe of the aorta, if it had croffed
that veffel to go to the cava.

A gentleman, whom I caftrated many years
fince, who trufted too much to his own refolution,
and refilling to have any one prefent to hold him,
except my afliftant, during the operation, moved
fo much, that the ligature which tied all the veffels
with the procefs together, flipt, and only tied the
procefs over the ends of the veffels : which being
perceived foon after the operation, I cut the liga-
ture, and took out the extravafated blood, and tied
the artery alone, which gave but little pain, and it
digefted off in a week's time, arid the wound being
afterwards Hitched, though the tefticle weighed a
pound, it was perfectly well in five weeks ; which
is in lefs time than the ligature fometimes requires,
to be digefted off, when the procefs and all the
veffels are tied together. However, if this cafe is
not fufficient to recommend doing this operation
by tying the artery only, it may be fufficient to
recommend extraordinary care in doing of it the
ufual way : for if the blood had found an eafy
paffage into the abdomen, the patient might have
bled to death.

* On the upper part of the tefticles, are hard
bodies called epididymi ; which are evidently the
beginning of the vafa deferentia.. I have un-

S ravelled

266 URINARY and GENITAL

ravelled them backward, in finglc veflels, and then
into more and imaller, like the excretory veflels
of other glands.

- Vafa deferentia are excretory ducts to cany the
elaborated feed into the veficulse feminales.. They
pafs from the epididymi of the tefticles, together
with the blood veflels, till they have entered the
mufcles of the abdomen, and then they pafs under
the peritona-nm, directly through the pelvis, to
the veficulce feminales.

• Veliciila? feminales are two bodies that appear
like veficles; they are feated under the bladder of
urine, near its neck ; ♦ they may be each of them
unfolded into one fmgle duel, which difcharges
into the urethra, by the fides of the roftrum gal-
linaginis, which is an eminence in the under fide
of the urethra near the neck of the bladder. In
thefe veficles, or ducts, the feed is repofited
againft the time of coition ; but in dogs there are
no fuch veficles, therefore nature has contrived a
large bulb in their penis, which keeps them coup-
led, feemingly againft their inclinations, till the
feed can arrive from the tefticles. The feed paffes
from thefe veficles in men, and even from the vafa
deferentia, in time of coition, through the proftatc
glands into the urethra, as in thole animals that
have no veficulse feminales ; for when the ducts
into the urethra are diftended, that, is the direct
courfe from the vafa deferentia, as well as from
the veficulse feminales.

Proftatae

PARTS of MEN. 267

Proftata? are two glands, or rather one, about
the fize of a nutmeg : they lie between the
veficulae feminales and penis, under the offa pubis,
almoft within the pelvis of the abdomen.. They
feparate a limpid glutinous humour which is
carried into the urethra by feveral duels, which en-
ter near thefe of the proftatae. This liquor feems
to be defigned to be mixed with the feed in the
urethra, in the time of coition, to make it flow
more eafily. If the venereal infection reaches the
proftate glands, it will fometimes make large ab-
fceffes, which are apt to form finufes, and even
make a paffage into the bladder. Upon the firft
attack of this difeafe, I have prevented all this
mifchief, by taking off the external fkin by in-
ciiion, as far as the hardnefs of the tumor ex-
tended, which draining very plentifully, the tumor
has fubfided, and the patient been eafily cured ; but
this cafe once becoming fiftulous, is very difficult
indeed. It often is cured by opening the finufes
and confuming the difeafed parts by efcarotics ; but
a much better and eaiier way, which I have often
done, is to cut out all the fiftulous and difeafed parts
at once.

Penis ; its fhape, fituation, and ufe, need no
defcription. It begins with two bodies named
crura, from the offa ifchia, which unite under
the offa pubis, and are there ftrongly connected
by a ligament. In its under part is the urethra,
through which both the feed and urine pafs ; its

S 2 fore

268 URINARY and GENITAL

fore part is called glans, the loofe fkin which cov-
ers it, prasputium, and the ftraight part of that fkin
on the under iide, fraenum. The urethra is lined
with a membrane filled with fmall glands that
feparate a mucus, that defends it againft the acri-
mony of the urine. Thefe glands are largeft near-
eft the bladder. Mr. Co wpe r defcribes three large
glands of the urethra, which he difcovered ; two
of which are feated on the fides of the urethra
near the ends of the crura penis ; to which he
adds a third, lefs than the other, feated almoft in
the urethra, a little nearer the glans than the for-
mer. All thefe glands have excretory du&s into
the urethra, and from them are fecreted all the
matter which flows from the urethra in a gonor-
rhoea, whether venereal or not. In the venereal
•infeciion, the urethra and the glands are firft in-
flamed by the contagious matter, that caufes a heat
of urine, which abates as foon as the glands^ begin
to difcharge freely ; but if by chance this difeafe
continues till any part of the urethra is ulcerated ;
the ulcer never heals without a cicatrix, which
conftricls the urethra, and makes that difeafe
which is vulgarly called a caruncle. The inner
texture of the penis is fpongy, like the inner tex-
ture of the fpleen, or the ends of the great bones.
It is ufually dlftinguiihed into corpus cavernofum
.penis, glandis, and urethras. The firft of thefe
makes part of the glans, and is divided its whole
length by a feptum ; the other two are compofed

of

PARTS of MEN. 209

of fmaller cells, and are but one body. On the
upper fide of the penis are two arteries, and one
vein called vena ipfius penis. The arteries are de-
rived from the beginnings of the umbilical arteries,
which parts never dry up, and the vein runs back
to the iliac veins. The vena ipfius penis, being
obftru&ed, the blood that comes by the arteries,
diftends the cells of the whole penis, and makes
it erecl: ; but to prevent mifchief from this me-
chanifm, there are fmall collateral veins on the fur-
face of the penis, that carry back fome blood all
the time the penis is erecl; ; but by what power
the vena ipfius penis is obftructed to erecl; the
penis, I cannot conceive, unlefs fmall mufcular
fibres conftricl; it. Some think the mufculi erec-
tores penis do it, by thrufting the penis againft
the os pubis ; but they feem . not feated conveni-
ently for fuch an office ; befides, if a preffure
from the lower fide of the penis is iufficient, an
artificial preffure, which may be much greater,
ihould, I think, produce the fame effect.

In the feed of men, and of other male animals,
Lewenhoeck, by the help of microfcopes, dis-
covered an infinite number of animals like tad-
poles, which he and others fuppofe to be men in
miniature, and that one of thefe being entered
into an egg in one of the ovaria (fee the next
chapter) conception is performed. But though
fcarce any one, that has made due inquiry, has
ever doubted of the exiitence of thefe animals,

yet

270 URINARY and GENITAL

yet there are many who object againft: this hypoth-
ecs ; and though I am inclined to think it true,
yet I will endeavour impartially to lay down the
principal objections and anfwers, that the reader
may judge for himfelf. The firft and ftrongeft
objection, is raifed from the feveral inftances that
have happened of mixed generation, where the
animal produced always appears to partake of both
kinds, as in the common cafe of a mule, which
is begot by an afs upon a mare ; when, according
to that hypothefis, they expect the animal pro-
duced from mixed generation mould be entirely
of the fame fpecies with the male animal ; as the
feeds of plants, whatever earth they grow in, al-
ways produce plants of the fame kind. Never-
thelefs, if we confider what influence women's
fears or longings frequently have upon their chil-
dren in utero, and how great a change caftration
makes in the fhape of any animal, we cannot
then wonder if the mother's blood, to which the
animal owes its nourifhment and increafe, from
the time of impregnation to the time of its birth,
mould be thought a fufficient caufe of refemblance
between thefe animals and their mothers. Anoth-
er objection is, that nature mould provide fuch
a multiplicity of thefe animals, when fo few can
ever be of ufeu To which it has been anfwered,
that in plants a very few of the whole that are
produced, fall into the earth, and produce plants ;
and as in plants the greatelt part of their feeds

are

PARTS of MEN. 271

are the food of animals, fo the greateft part of
the animalculae may as well live a time to enjoy
their own exiftence, as any other animal of as low
an order. The laft objection is their fhape, which
I think will appear to have no great weight,
when we confider how the eggs of flies produce
maggots, which grow up into flies ; and the tad-
pole produced from the egg of a frog, grows into
a form as different from a tadpole as the form of
a man : and if thefe animals had produced fo few
at a time, as that their young might have under-
gone this change in utero, it is highly probable,
that we ihould not fo much a's have fufpe&ed thefe
analogous changes. But how the animalculre
themfelves are produced, is a difficult queftion,
unlefs by equivocal generation, feeing none of
them appear to be in a ftate of increafe, but all
of a fize. ^

In a boy that died of the (tone, I found a
double ureter, each part being dilated to an inch
diameter ; the pelvis in each kidney to twice its
natural bignefs, and the tubuli urinarii, each as
large as the pelvis.

In a man that had never been cut for the ftone,
I found the ureters dilated in fome places to four
inches circumference, and in others but little dilat-
ed, and a ftone that I found in the bladder was
lefs than a nutmeg, which mult have fallen in fev-
eral pieces, or both ureters could not have been
dilated. From this, and other like obfervations,

I think

272 GENITAL PARTS of WOMEN.

I think it appears, that the great fize to which
the ureters are ufually extended, in people who
are troubled with the ftone, is owing to fmall
ftones which flick at the entrance into the blad-
der, until the obftructed urine, which dilates the
ureters, can force them into the bladder.

I have in feveral fubje&s found one kidney al-
moft confumed, and once a man with but one kid-
ney ; and I have feen lymphatics in a difeafed?
tefticle, as large as a crow-quill.

CHAP. It

Of the Genital Parts of Women.

• 1 HE external parts are the mons veneris, which
is that rifing of fat covered with hair above the
rima magna upon the os pubis, the great doub-
ling of the ikin on each fide the rima called labia,
and within thefe a letter doubling named nymphae..
Thefe help to clofe up the orifice of the vagi-
na. The nymphae are ufually faid to ferve to de-
fend the labia from the urine ; but I do not fee
how the labia ftand more in need of fuch a de-
fence, than the nymphas themfelves.
• Clitoris is a fmall fpongy body, bearing
fome analogy to the penis in men, but has no
urethra.. It begins with two crura from the oifa
ifchia, which uniting under the offa pubis, it

proceeds

GENITAL PARTS of WOMEN. 273

proceeds to the upper part of the nympha?, where
it ends under a fmall doubling of fkin, called prse-
putium ; and the end which is thus covered is cal-
led glans. This is faid to be the chief feat of
pleafure in coition, in women, as the glans is in
men.

A little lower than this, juft within the vagina,
is the exit of the meatus urinarius.
• Vagina is feated between the bladder of urine
and the inteftinum rectum.. The texture of it
is membranous, and its orifice is contracted with
a fphincter (vid. mufc. fphincter vaginas) but the
farther part is capacious enough to contain the pe-
nis without dilating. Near the beginning of the
vagina, immediately behind the orifice of the
meatus urinarius, is conftantly found in children
a valve called hymen, which, looking towards the
orifice of the vagina, clofes it ; but as children
grow up, and the fphincter vaginas grows ftrong
enough to contract and clofe the orifice of the
.vagina, this valve becoming ufelefs, ceafes to in—
creafe, and is then known by the name of carun-
culse myrtiformes. There have been a few in- fr 1
fiances in which the edges of this growing together,
it continued unperforate, until it has been necefla-
ry to make an incifion to let out the menfes. The
inner part of the vagina is formed into rugae,
which are largeft in thofe who have not ufed cop-
ulation ; and leaft in thofe who have had many
children. Under thefe ruga? are fmall glands,

whofe '

r

374 GENITAL PARTS of WOMEN.

whofe excretory ducts are called lacunas : thefe
glands feparate a mucilaginous matter to lubricate
the vagina, efpecially in coition : and are the feat
of a gonorrhoea in this fex, as the glands in the
urethra are in the male.

• Uterus is feated at the end of the vagina ; it
is about one inch thick, two broad, and large
enough to contain the kernel of a hazel-nut ; but
in women that have had children, a little larger. .
Its orifice into the vagina is called os tincse, from
the refemblance it bears to a tench's mouth. It
has two round ligaments which go from the fides
of it to the groins through the oblique and trani-
verfe mufcles of the abdomen, in the fame man-
ner as do the feminal veflels in men. This way
the gut paffes in a hernia inteftinalis in women
(vid. mufculi abdominis.) Some authors mention
iigamenta lata, which are nothing but a part of
the peritonaeum. Near the fides of the uterus lie
two bodies called ovaria ; they are of a depreffed
oval figure, about half the fize of men's tefticles,
and have fpermatic veflels ; they contain fmall pel- .
lucid eggs, from which they have their name.
There are two arteries and two veins, which pais
to and from the ovaries or teftes, in the fame
manner that they do in men ; but make more
windings, and the arteries dilate more fuddenly,
in proportion as they are fhorter. Thefe arteries
and veins detach branches into the uterus and fal-
lopian tubes, and not only make communications

betwixt

GENITAL PARTS of WOMEN. 275

betwixt the artery and vein on one fide and thofe
of the other, but alfo with the proper veffels of the
uterus, which are detached from the internal iliac
arteries and veins. From thefe veffels in the in-
fide of the uterus, the menftrual purgations ore
made in women, and fomething of the fame kind
in brutes, as often as they delire coition. One ufe
of thefe purgations is, to open the veifels of the
uterus, for the veffels of the placenta to join to
them. Many authors have imagined, that there
mud be fome evacuations analogous to this, in
men, which I cannot fee the neceffity of; but,
on the contrary, I believe that men's not having
fuch evacuations, is the true reafon why their bod-
ies grow larger and ftronger then women's : and
their continuing to grow longer before they are fit
for marriage, I alfo take to be the true reafon
why there are more males born than females, in
about the proportion of thirteen to twelve ; for
women being fooner fit for marriage than men,
fewer will die before that time, than of men.
* Near the fides of the ovaria are feated the
tubas fallopianas, one end of which is connected to
the uterus and the fide of the ovarium by a mem-
brane, the other end is loofe, and being jagged is
called morfus diaboli/. Among thefe jaggs is a
fmall orifice which leads into the tube, which
near this end is about a quarter of an inch diame-
ter, and thence, growing gradually fmaller, paffes
to the uterus, and enters there with an orifice

about

ij6 GENITAL PARTS of WOMEN.

about the fize of a hog's bridle. The ufc of thefc
tubes is to convey the male feed from the uterus to
the ovaria, to impregnate the eggs for conception!
yet they appear fo ill adapted to this end, tha
many have fuppofed there muft be fome other
paffage from the uterus to the ovaria : but when
we confider the cafe of conceptions found in tl>
tubes, and the exact analogy between thefe and
the tubes of birds, where we have the moft un-
deniable proofs of the feed going through the
tube, and of the eggs being impregnated that way,
and of the eggs coming from the ovarium through
the tube, and feemingly with much greater dif-
ficulty than in women ; and befides, how fre-
quently a matter like the male feed (which I fup-
pofe is feed) is found in the fallopian tubes of
women, as I have found in executed bodies, and
in a common whore that died fuddenly, it appears
to me almoft certain, that the feed goes through
the fallopian tubes to the ovaria to impregnate
eggs, and comes back through the fame tubes to
the uterus. I have feen in a woman both the fal-
lopian tubes unperforated, which, upon the fore-
going hypothefis, muft have caufed barrennefs,
and feed lodged in thefe tubes may have the fame
effect ; which I take to be often the cafe of com-
mon whores, and women that ufe coition too fre-
quently ; and perhaps the fat in the membrane
that connects the ovaria to the tubes, may in very
fat women fo keep thefe tubes from the ovaria as

to

GENITAL PARTS of WOMEN. 277

to interrupt impregnations ; and befides thefe
cafes, too much or too little of the menfes may
deftroy or interrupt conceptions ; but the latter
cafe, efpecially in young women, is very rare.
From fuch caufes as thefe, and not from imbecil-
ity, I imagine it is that barrennefs oftener pro-
ceeds from women than men ; and though women
do not propagate to fo great an age as men, it is
not, I believe, for want of being impregnated,
but from their menfes ceafing, and thofe veffels
being clofed which fhould nourilh the foetus after
the impregnation, as if on purpofe to prevent the
propagation of a feeble and infirm fpecies. And
from this confideration, one cannot but think that
the perfection of the foetus, notwithstanding it is
firft formed in the male feed, depends more upon
the female than the male ; or elfe that nature would,
for the fake of the fpecies, have been careful to
hinder men as well as women from propagating in
a declining age.

CHAP.

( • *7« )

CHAP. III.

Of the Foetus in Utero.

•THE foetus in utero is involved in two coats,
viz. chorion, which is external, and amnion, which
immediately inclofes the foetus.. They contain
a quantity of liquor, which is a proper medium
for fo tender a being as the foetus to reft in, and
partly fecures it from external injuries, as the aque-
ous humour does the chryftalline in the eye j and
when the membranes burft at the time of produc-
tion, this humour lubricates the vagina uteri, to
render the birth lefs difficult. And feeing the
fromach of a foetus in utero is always full of a
fluid, like what is contained in the amnion, and
the guts not without excrements ; we may fuppofe
that this fluid is frequently, during the time of
geftation, iwallowcd by the foetus, if not for nour-
iihment, at leaft to keep thefe parts in ufe, and to
flow through the la&eals, as a quantity of blood
from the right ventricle of the heart flows through
the Rings before the birth to keep open thofe
paffages till the birth, there being after that time
no other way of receiving nourishment, and that
the feces found in the guts of a foetus are thofe
parts of this fluid that were taken in at the mouth,
and were too grofs to enter the la&eals. Yet I
own it takes off very much from the probabil-
ity of the opinion of the foetus's imbibine this

liquor,

FCETUS in UTERO, 279

liquor, that, if I am rightly informed, fome who
have been born with mouths and noftrils unper-
forate, have had fuch fluids and excrements in the
interlines that other foetus's have, which mult be
confefTed, may be derived from the falivary glands
and from the liver, &c. The following curious
paflage was fent-me by Mr. Monro. " This li-
" quor contributes nothing to the nourimment of
" the foetus, for thefe reafons ; firft, becaufe, as
" you have well obferved, vaft numbers of in-
" ftances might be produced, where no paflage
" was to be found for it : I {hall give you one I
" faw myfelf in the Hotel de Dieu at Paris, in
" 1718.

" Mary Guerlin brought forth two children,
" one a complete girl, the other had neither head,
" neck, arms, heart, lungs, ftomach, fmall guts,
" Uver, fpleen, or pancreas, yet the great guts,
" the organs of urine and generation of a female,
" and lower extremities were perfect, and of a na-
" tural growth ; the umbilical vein, after entering
" the abdomen, fplit into a great many branches,
" which were diftributed to the feveral parts in
" its abdomen. Though it is true that foon af-
" ter conception, the liquor in the amnion, and
" that in the ftomach of the fcetus referable one
" another pretty near, yet afterward they differ
"exceedingly; for the liquor in the ftomach is
" ft ill gelatinous, thick, and without acrimony,
" while the other becomes thinner and more acrid ;

t; whereas,

280 FCETUS in UTERO.

" whereas, had the foetus conftantly fwallowed
" this liquor, the cafe would have been quite op-
" pofite ; nay, often it has happened that thefe
" waters (as they are commonly called) have been
." found quite corrupted, ftrongly fetid, and ex-
" tremely fliarp, while the fcetus, except the in-
" juries which the external parts received, was
" well and found ; witnefs the example mentioned
"by Bellinger, of a woman who was cured
" of a virulent gonorrhoea during her going with
" child. And farther, by Malpighius's delinea-
" tions of the pullus in ovo, it appears to be evi-
" dent that the afitellus ferves the fame purpofe as
" the placenta does in viviparous animals, to con-
" vey the albumen attenuated by incubation into
" the blood veffels of the chick, and that none of
" the albumen does pafs through the faccus col-
" liquamenti."

• Befides thefe coats, in a cow and many other
animals, we find a membrane called alantois ; it
is incloied by the chorion together with the am-
nion, and contains a quantity of water which it re-
ceives from the bladder of urine by the urachus. . Its
ufe items to be to contain the urine, that it might
not by the common paffage be emptied into the li-
quor of the amnion, of which the fcetus, I am in-
clined to think, is frequently drinking.

Whether an alantois is to be found with a Im-
parl foetus or no, anatomifts are not agreed, and
1 cannot give my opinion, having never had a

fuflicient

FCETUS in UTERO. 281

fufficient opportunity to inquire. But furely chil-
dren having an urachus, one cannot well doubt of
an alantois. I have been informed by a gentleman,
whofe probity I can fufficiently rely on, that he
had feen a child that had no external genital parts,
and made water through the navel. At Henley
upon Thames, there is now living a bargeman's
child about ten years old, of which I had the like
account ; but upon examination I found the un-
perforated glans with its fraenum immediately be-
low the place of the navel, and the urine ilfued
out by drops between this and the belly, in the
place which I fuppofe was the navel, but it was
fo much excoriated, that I could make no certain
judgment about it. In the uterus of a cow with
two calves, I found they had but one chorion,
but each an amnion and alantois diftind: ; but the
cotyledons, which are analogous to the placenta of
the human foetus, were pretty much in common t®
the umbilical blood veffels of both.
' The placenta, or womb-liver, is a mafs of
blood veffels feated on the outfide of the chorion,
being compofed of the extreme branches of the
umbilical vein and arteries, which are, for the
compofition of this part, divided into exceeding
fmall branches, to join alike number of the men-
ftrual veffels of the uterus ; - which veffels- of the
uterus are made numerous rather than large, that
the feparation of the placenta from them may nob
be attended with a flux of blood fatal to the mo-

T ther ;

282 FGETUS in U TE KG.

tUer ; for the fides of little veflels foon collapfc
And clcfe, and they are more eaiily Hopped, being
comorefied by the uterus itfelf as it ihrinks, which
it begins to do from the time of the birth ; but
when the placenta is feparated before the delivery,
whether untimely or not, thefe veiTels bleed until
the uterus is dif charged of the foetus. The figure
of the placenta is circular, and at its greateft
Growth about two inches thick, and fix or feven
in diameter.

• The arteries and veins of the uterus of the mo-
ther, by which the menftrual purgations are made,
are joined to the umbilical arteries and veins in the
placenta of the foetus, the arteries of the uterus to
the veins in the placenta, and the veins in the
uterus to the arteries of the placenta : « by thefe
veflels a large quantity of blood is continually
flowing from the mother to the foetus and back
again ; but for what end fiich a quantity flows
continually, and back again, I cannot conceive,
unlefs it is that the foetus not breathing for itfelf,
it is neceifary that as much blood of the mother
ihould flow continually to the foetus, as can leave
enough of air, or whatever our blood receives in
the lungs, for the fcetus ; and perhaps what nutri-
tious juices the foetus receives, require a great deal
of blood to convey them, they being but a fmall
part of the blood. And though the blood pafles
^plentifully between the mother and the foetus,
yet the communications are not fo obvious as they

are

FOETUS in UTERO. 283

are between the arteries and veins in the fame
body ; which makes fome think the communica-
tion is no: made by modulations of veffels, but that
the foetus is nourished from the placenta in a vege-
table m inner 3 but, I own, I am not of this opin-
ion. The navel-ftring or umbilical blood veflels,
between the placenta and the navel, are about two
feet long, that the foetus may have room to move
without tearing the placenta from the uterus,
which being done too foon, from whatever caufe,
occasions a. mifcarriage. Thefe veflels, viz. two
arteries and one vein, twift about each other, par-
ticularly the arteries about the vein, and are con-
tained in one common coat together with a vefTel
called urachus, which arifes from the top of the
bladder of urine, and ends in the membrana alan-
tois ; the umbilical vein goes from the navel di-
rectly into the liver, and there enters the great
trunk of the vena ports. Near which entrance
there goes out the ductus venofus to the great
trunk of the cava, which carries part of the blood
that is brought by the umbilical vein, that way
into the cava, while the reft circulates with the
blood in the porta, the whole of it not pafling
through the ductus venofus, as is generally believed,
but a great part of it into branches of the porta,
in the liver, otherwife there need be no commu-
nication between the umbilical vein and the porta.
When the umbilical vein is flopped, it becomgp
a ligament, and the ductus venolus foon fhrinks
T 2 and

284 F GET US in UTERO.

and almofl difappears, having no longer any blood"
flowing through it ; and even the porta itfelf
within the liver, from whence only blood could
pafs after the birth into the ductus venofus, has
lefs blood flowing through it for fome time than
it had before the birth, it receiving much blood
before the birth from the umbilical vein. The
blood which flows from the mother to the foetus
by the umbilical vein, is returned, all but a fmall
quantity, which is refer ved for nutrition by the
two umbilical arteries, which arife from the inter-
nal iliac arteries, and paffing by the outiides of
the bladder go directly to the navel, and placen-
ta ; thefe with the urachus being fhrunk up after
the birth, lofe much of their appearance, efpecially
near the navel, where they are fometimes not to
be diftinguifhed.

Part of the blood before the birth, and not
the whole quantity, as is generally thought, which
is brought by the afcending cava to the right au-
ricle, paffes at once throu'gh the foramen ovale into
the left auricle, and the reft flows into the right
ventricle with the blood of the defcending cava,
and thence into the pulmonary artery, where about
one half flows into the lungs, 2nd the other half
directly into the aorta by the ductus arteriofus,
which lies between the pulmonary artery and the
aorta, which after the birth is called ductus ar-
tWiofus in ligamentum vernas. The better to ex-
plain this contrivance, I will call the quantity of

blood

FCETUS in UTERO. 2S5.

blood flowing through the afcending cava in a
given time, four ; and that which flows through
the defcending cava, two : then let two of the
quantity in the afcending cava flow into the right
auricle, it will then with the two received from
the defcending cava have the quantity four ; which
being thrown from the right ventricle into the
pulmonary artery, the quantity two is thrown into
the aorta by the ductus arteriofus, and the fame
quantity into the lungs by the pulmonary branches ;
then the quantity returning from the lungs to
the left auricle, will be two in the fame given
time, which being added to the two which flowed
through the foramen ovale, in the fame time
there will be conftantly, the fame proportions re-
ceived into each ventricle, at every diaftole of the
ventricles, as after the birth. Now if the blood,
flowing through the afcending cava joined by that
from the umbilical vein, was but equal to that
flowing through the defcending, let each of them
be called two and let all the blood of the afcend-
ing cava go through the foramen ovale ; then the
blood which the left ventricle would receive,
would exceed that which flows into the right, by
the whole quantity which flows from the lungs
in the fame time ; but the afcending cava convey-
ing more blood than the defcending cava, the ex-
cefs in the left ventricle would be yet greater. If
the proportions, which I have taken for the eaficr
computing, were perfectly right, as I am fure

they

286 FCETUS in UTERO.

they are nearly, then the quantity flowing into the
left ventricle would be to that flowing into the
right at the fame time as five to two, if all the ai-
cending blood went through the foramen ovale.

And though after the birth the left ventricle of
the heart is only employed in throwing blood into
the aorta, and the right wholly employed in cir-
culating the blood through the lungs ; yet before
the birth, all the blood thrown out by the left ven-
tricle, and about half the blood thrown out of
the right ventricle, being thrown into the aorta,
and the other part only through the lungs, it fol-
lows, that the whole force exerted by the left
ventricle, with about half that of the right, is
employed in throwing blood into the aorta, while
that diftributes blood through the whole foetus
and to the mother : but after the birth, when the
blood is to be no longer carried from the foetus
to the mother, the left ventricle becomes fufheient
for the circulation through the foetus, and a new
occafion immediately arifes for that additional
power, which before was neceffarily employed
in throwing blood into the aorta ; for the whole
mafs of blood now being to be circulated through
the lungs, the ductus arteriofus clofes, and the
right ventricle muft throw ail the blood it receives
into the lungs, there being no longer any paffagc
into the aorta. It is fuppofed that the inflation of
the lungs at the birth, prefently alters the pofition
pf the ductus arterioles, fo as to obfirucl it ; which

account

FCETUS in UTERO. 287

account is indeed mechanical, but, I think, not
true, becaufe I can neither difcern that the pofition
of this vefTel is altered, nor its furface comprefied :
but I rather think that immediately upon the
birth, there being no blood carried off from the
foetus to the mother, and the left ventricle being
fufficient to fill the aorta and its branches with
blood, as I have fhewn before, there is no longer
room for any blood from the right ventricle ;
wherefore the blood from the right ventricle will
be forced into the lungs, where the paflage is
now made eafy, as I imagine, by their being in-
flated ; and the ductus arteriofus, having the bloo'i
no longer forced into it, fhrinks, and in time al-
moft difappears. This duel: being flopped, the
valve of the foramen ovale foon flops that pafTage,
it being on the fide of the left auricle (or that
mufcular bag, which is the larked part of that
auricle) which being much the ftrongeft, the valve
muft be preffed more on that fide than the other,
by the blood, in the time of the fyftole of the au-
ricle ; and it is as evident, that in the diaftole of
the auricle, there muft be more preflure to open
that than the right, it being a ftronger mufcle,
or elfe there could have been no reafon for having
the left auricle ftronger than the right, in propor-
tion to their ventricles. Sometimes this valve does
not quite cover the foramen, in which cafe a fmall
quantity of the blood may poflibly flow from the
left auricle to the right, and fo circulate twice

through

288 FOETUS in UTERO.

through the lungs to once through the body, but
none could flow from the right to the left and
efcape the lungs, which might be of bad conie-
quence. Some have imagined, that men, who
have this pafTage open, cannot be drowned : but
though this paffage is fometimes found open, no
man has been yet feen, that wc have ever heard of,
that could not be drowned. I have feen the fo-

■i open in a man that was hanged, to whom
one might juftly exped: it mou^d have been asufe-
ful as in the cafe of fubmerfion in water. Many
writers have fuppofed, that this foramen is open in

i.ibious animals, and in fuch fifties as have
two auricles, two ventricles, and lungs like land
animals, without gills, which in other filh are
analogous to lungs. I have diffe&ed a porpoife,
which is of this kind, and found this foramen
clofed, but the great veins were vaftly large in pro-
portion to the bulk of the animal ; whence I con-
jectured, their blood was accumulated in their
veins, while they kept under water, and by that
means the lungs efcaped being opprefled with
blood ; which conjecture feemed to me the more
probable, fmce all animals of this kind are able to
abide the leaft time under water, when their blood
is mofl expanded with heat, But upon the dif-
fe&ion of an otter, whole foramen ovale was alfo
clofed, I found the veins nothing dLTering from
thofe of other animals. In a water-tortoife, which
J had an opportunity of examining, with that

moft

FCETUS in UTERO. 289

molt dexterous and indefatigable anatomift, Dr.
Douglas, I found the two ventricles of the
heart but half divided by a feptum, and in the
beginning of the pulmonary artery feveral ftrong
mufcular, rings, a little diftance from each other,
each of which, by contrading, would be capable
of refilling a part of that blood which otherwife
would have been thrown into the lungs, when
they were under water; and this blood fo ob-
ftru&ed muft neceflarily be thrown into the aorta,
the two ventricles being in a manner one com-
mon cavity ; and when they are out of the water,
this communication of ventricles will fuiTer but
little confufion of the blood which flows into the
ventricles, becaufe each ventricle receiving and
difcharging the fame quantity of blood, at the fame
time, they will balance each other, and thereby
fuch a mixture will be very much prevented.
Mr. Monro obferves, that the water-tortoife has
very large lungs, confifting of larger veficles than
land animals, and that they receive a great quan-
tity of air to furnilh that je ne fcai quoi fo necef-
fary for the life of animals ; the fame thing I have
obferved in frogs.

As to the reafon of women's bringing forth at
the ufual time ; it has been faid, that at that time
the head of the child begins to be fpecifically hea-
vier*than the reft of the body, and therefore muft
fail loweft in the fluid it lies in, which being an
uneafy pofture, makes the child ftruggle, and

bring

ngo Of the EYE.

bring on the labour. But it is not true, that the
head then alters its fpecific gravity ; or, if it did,
there is feldom fluid enough in the amnion for this
purpofe ; and befides, this could only happen right
in one pofture, and would ufually happen wrong
in brutes.

CHAP. IV.

Of the Eyz.

1 HE figure, fituation, and ufe of the eyes,
together with the eye-brows, eye-lafhes, and
eye-lids, being well known, I need only defcribc
what is ufually fhewn by differing. The orbit
of the eye, or cavity in which it is contained,
is in all the vacant places filled with a loofe fat,
which is a proper medium for the eye to reft in,
and ferves as a focket for it to be moved in. In
the upper and outer part of the orbit, is feated the
lacrymal gland. Its ufe is to furnim at all times
water enough to wafh off dufi, and to keep the
outer furface of the eye moid, without which
the tunica cornea would be lefs pellucid, and the
rays of light would be difturbed in their paflage ;
and that this liquor may be rightly difpofed of, we
frequently clofe the eye-lids to ipread it eqd|lly,
even when we are not confeious of doing it. At
the inner corner of the eye, between the eye-lids,

ftands

Or the EYE. 291

Hands a caruncle,, which feems to be placed to
keep that corner of the eye-lids from being totally
clofed, that any tears or gummy matter may flow
from under the eye-lids, when we ileep, or into
the puncta lacrymalia, which are little holes, one
in each eye-lid, near this corner, to carry off into
the ductus ad nafum any fuperflucus tears.

* The firft membrane of the eye is called con-
junctiva ; it covers fo much of the eye as is called
the white, and being reflected all round, it lines
the two eye-lids ; » it being thus returned from the
eye to the infide of the eye-lids, it effectually hin-
ders any extraneous bodies from getting behind the
eye into the orbit, and fmooths the parts it cov-
ers, which makes the friction lefs between the eye
and the eye-lids. This coat is very full of blood
yefTels, as appears upon any inflammation.

• Tunica fclerotis, and cornea, make together
one firm cafe of a proper form, for the ufe
of the other coats and humours. The fore part
of this ftrong cGat being tranfparent, and like
horn, is called cornea, and the reft fclerotis. * Un-
der the cornea lies the iris, which is an opaque
membrane, like the tunica choroides, but of dif-
ferent colours in different eyes, fuch as the eye
appears, as grey, black, or hazel ; for being feat-
ed under the tunica cornea, it gives fuch an ap-
pearance to that as it has itfelf. The middle of
it is perforated for the admiffion of the rays of
light, and is called the pupil. Immediately under

the

292 Of the EYE.

the iris lie the proceflus ciliares, like radial lines
from a leffer circle to a greater. When thefe pro-
cefTes contract, they dilate the pupil to fuffer more
rays of light to enter into the eye ; and the con-
trary is done by the circular fibres of the iris,
which a& as a fphin&er mufcle : but thefe changes
are not made with great quickncfs, as appears from
the eyes being oppreiTed with a flrong light for
fome time, after we come out of a dark place,
and from the' contrary effecT: in going fuddenly
from a light place to a dark one. And as the pu-
pil always dilates in darker places, to receive more
rays of light, fo when any difeafe makes fome of
thofe rays ineffectual, which pafs through the
pupil, it dilates as in dark places to admit more
; therefore a dilated pupil is a certain fign of
a bad eye, and this may be difcerned ufually fooner
than the patient difcerns any defect in vifion. In
men the pupil is round, which fits them to fee
every way alike ; it is alfo round in animals that
are the prey both of birds and healls. But gra-
minivorous brutes, that are too large to be the prey
of birds, have it oblong horizontally, .which fits
them to view a large fpace upon the earth ; while
animals of the cat kind, who climb trees and prey
indifferently on birds or animals that hide in the
earth, have their pupils oblong the contrary way,
which fits them belt to look upward and dfljra-
ward at once. Befidcs thefe there are other ani-
mals whofe pupils are in thefe forms, but in lefs

proportions,

Of the E Y E. 293

proportions, fo as beft to fit their ways of life.
Immediately under the fckrotis, is a membrane of
little firmnefs, called choroides. In men it is of
a nifty dark colour, iuch as will bury almoft ail
the rays of light, that pafs through the tunica
retina, which if it were of a brighter colour,
would reflect many of the rays upon the retina,
and make a feccnd image upon the firft fomewhat
lefs, and lefs diftinct, but both together flronger ;
which is the cafe of brutes of prey, where a great
part of this coat is perfectly white, which makes
them fee bodies of all colours in the night better
than men, for white reflects all colours : but
brutes that feed only on grafs, have the fame parts
of this membrane of a bright green, which enables
them alfo to fee with lefs light, and makes grafs
an object that they can difcern with greater!:
ftrength. But thefe advantages in brutes necefla-
rily deftroy great accuracy in vifion, which is of
little or no ufe to them, but to men of great confe-
quence. This green part of the tunica choroides
in animals that graze, may properly be called mem-
brana uvea, from its refemblance in colour to an
unripe grape. But in men's eyes only a white
circle round the back fide of the choroides near the
cornea, is called uvea.

i Immediately under the tunica choroides
lies the tunica retina, which is the optic nerve
expanded and co-extended with the choroides.*
Rays of light (biking upon this membrane, the

fenfation

294 ° r THE islt-iL

fenfation is conveyed by the optic nerves, to the
commen fenforium the brain. Thefe nerves do not
enter at the middle of the bottom of the eyes,
but nearer the nofe ; for thofe rays of light being
ineffectual for virion that fall upon the entrance of
the optic nerves, it is lit they mould fo enter, as
that the fame object or part of any object mould
net be unperceived in both eyes, as would have
been the cafe, had they been otherwife inferted ;
which appears from a common experiment of part
of an object being loft -to one eye, when we are
looking towards it with the other fhut. I know
a gentleman, who having loft one eye by the fmall-
pox, and going through a hedge, a thorn unfeen
(probably from this caufe) ftruck the other and
put it out. The two optic nerves, foon after they
arife out of the brain, join, and feem perfectly
united ; yet from the following cafe I am not
without fufpicion of their fibres being preferved
diftinct, and that the nerve of each eye arifes
wholly from the oppolitc fide of the brain, or
elfe that the other nerves throughout: the body arife
from the brain, and medulla oblongata, on the
fides oppofite to thofe they come out of. A fol-
dier, who was my patient in the hofpital about
five years fince, had, by a puih with a broad
fword, his left eye raifed in the orbit, which I
replaced with my ringers ; it was prefently follow-
ed with excefhve pain in the right fide of the
head only ; and a lofs of the Ic-nfc of feeling and

motion

Of the E Y E. zg$

motion in both the right limbs ; the fenfe of feel-
ing he recovered by degrees in about a month, and
foon after began to recover their motion, but was
twelve months before he could walk, and lift up
his hand to his head ; and in about two years re-
covered all but the fight of the wounded eye,
which indeed did not appear perfect. In fifh
thefe nerves arife diftinct from the oppofite fides
of the brain, and crofs without uniting ; but as
thefe animals have their eyes fo placed, as not to
fee the fame object with both eyes at once, where-
as animals, whofe optic nerves feem to unite, do
fee the fame object with both eyes at once, one
would fufpect that in one they were joined to
make the object not appear double, and in the
other diftinct, to make their two eyes (as they are
to view different objects at the fame time) inde-
pendent on each other : and yet from the follow-
ing cafes, the feeing objects fmgle feems not to
depend upon any fuch union, nor from the light
ftriking upon correfponding fibres of the nerves,
as others have believed, but upon a judgment from
experience, all objects appearing fmgle to both
eyes in the manner we are moll ufed to obferve
them, but in other cafes double ; for though we
have a diftinct image from each eye fent to the
brain, yet while both thefe images are of an ob-
ject feen in one and the fame place, we conceive
of them as one ; fo when one image appears to
the eyes (when they are diftorted or wrong di-
rected)

296 Of the E Y E.

recied) in two different places, it gives the idea of
two ; and when two bodies are feen in one place,
as two candles rightly placed, through one hole
in a board, they appear one. But cafes of this
kind being too numerous, I will conclude with
one very remarkable, and, I think, much in favour
of this opinion. A gentleman, who from a blow
on the head had one eye diftorted, found everv
object appear double, but by degrees, the moft fa-
miliar ones became iingle, and in time, all objects
became fo, without any amendment of the diftor-
tion.

- Thfrinfide of the eye is filled with three hu-
mours,*called aqueous, cryftaliine, and vitreous..
The aqueous lies foremoft, and feemS chiefly of
ufe to prevent the cryftaliine from being -eafrly
bruifed by rubbing, or a blow ; and perhaps it
ferves for the cryftaliine humour to move forward
in, while we view near objects, and backward for
remoter objects ; without which mechanifm, or,
in the plaqe of it, a greater convexity in the cryftal-
iine humour in the former cafe, and a lefs con-
vexity in the latter, I do not imagine, according
to the laws of optics, how we could fo diftinctly fee
objects at different diitances. However it is in
land-animals, I think we may plainly fee that
fifh move their cryftaliine humour nearer the bot-
tom of the eye when they are out of water, and
the contrary way in water ; becaufe light is lefs
refracted from water through the cryftaliine hu-
mour

Of the EYE. 297

mour than from air. Some have faid, that am-
phibious animals have a membrane like the mem-
brana nidtitans of birds, which ferves them as a
lens in the water. I have examined the eye of a
crocodile, which Sir Hans Sloan kept in fpir-
its, and I found this membrane equally thick
and denfe, and confequently unfit for this pur-
pofe, or, I believe, any other, except that obvious
one, of defending the eye from the water. Next
behind the aqueous humour lies the cryftalline ; its
fhape is a depreffed fpheroid, it is difdnclly con-
tained in a very fine membrane called aranea.
The ufe of this humour is to refract the rays of
-light which pafs through it, fo that each pencil of
rays from the fame point of- any object may be
united upon the retina, as in a camera obfcura,
to make the ftronger impremon ; and though by
this union of the rays a picture inverted is made
upon the retina, yet furely it is the impulfe only
of the rays upon the retina that is the caufe of
vifion ; for had the colour of the retina been black,
and confequently unfit to receive fuch a picture,
would not the impulfe of light upon it have been
fufficient for vifion ? or would fuch a picture, if
it could have been made without any impulfe,
have ever conveyed any fenfation to the brain ?
Then if the impulfe of light upon the retina, and-
not the image upon the retina, is the caufe of vi-
fion ; when we inquire why an image inverted in
the eye appears otherwife to the mind, might

U we

298 Of the EYE.

we not expect to find the true caufe from confid-
ering the directions in which the rays flrike the
retina, as we judge of ahove and helow from a
like experience, when any thing ftrikes upon any
part of our bodies ? Neverthelefs, in viewing an
object through a lens, we conceive of it as in-
verted ; when as in receiving the impulfes of light
in the fame manner, and having the picture on
the retina in the fame attitude, when we ftand
on our heads without the lens, we have not
the fame, but the contrary idea of the pofition of
the object. Though I have confidered this hu-
mour only as a refractor of light, yet the firfl and
greateft refraction is undoubtedly made in the cor-
nea ; but it being concavo-convex, like glafTes of
that kind, while one fide makes the rays of light
converge, the other diverges them again. The
fame thing alfo may be obierved of the aqueous
humour, which is indeed more concave than con-
vex ; but when the cryftalline humour is removed
in the couching a cataract, the aqueous poffeffes its
place and becomes a lens ; but that refracting light
lefs than the cryftalline, whofe place and fhape it
partly takes, the patient needs a convex glafs to
fee accurately. In fome eyes, either this humour
being too convex or too diftant from the retina,
the rays unite too foon, unlefs the object is held
very near to the eye, which fault is remediable
by a concave glafs ; as the contrary fault, common
to old perfons, is by a convex glafs. If the eye

had

Of the EYE. 299

had been formed for a nearer view, the object
would often obftruct the light ; if it had been
much farther, light enough would not commonly
have been produced from the object to the eye.
In fiih the cryftalline humour feems a perfect
fphere, which is necelfary for them, becaufe light
being lefs refracted from water through the cryf-
talline humour than from air, that defect is com-
penfated by a more convex lens. The vitreous
humour lies behind the cryftalline, and fills up the
greater! part of the eye : its fore fide is concave
for the cryftalline humour to lodge in, and its
back fide being convex, the tunica retina is fpfead
over it ; it ferves as a medium to keep the cryftal-
line humour and the retina at a due diftance.

The larger animals having larger eyes, their
organs of viiion, like a microfcope with a large
lens, are fit to take in a greater view, but in that
view things are not fo much magnified ; in lefTer
animals a fmall fpace is difcerned, fuch as is their
fphere of action, but that greatly magnified, not
really fo in either cafe, but comparatively, for
vifion fhews not the real magnitude of objects,
but their proportions one to another. Fiih have
their eyes, and particularly their pupils, larger
than land animals, becaufe there is lefs light, and
that not fo far diftributed in water as in the air.
In all inflammations in the eye, the utmoft hafte
mould be made, by bleeding, purging, abftinence,
&c. to get rid of the inflammation, becaufe a con-
U 2 tinued

300 Of the EYE.

tinued inflammation feldom fails to make white
opaque fears in the cornea, which caufe dimnefs
if not blindnefs ; and no eye- water with powders
in it fhould ever be put upon the eye, becaufe
none can be made fine enough.

An account of obferv aliens made by a young gentle-

n 'who was born blind, or lojl his fight fo early

that he had no remembrance of ever having feen,

and was couched between thirteen and fourteen

years of age,

THOUGH we fay of this gentleman that he
was blind, as we do of all people who have ripe
cataracts, yet they are never fo blind from that
caufe but that they can difcern day from night,
and for the moil part, in a ftrong light, diftinguifh
black, white, and fcarlet ; but they cannot per-
ceive the fhape of any thing ; for the light, by
which thefe perceptions are made, being let in ob-
liquely through the aqueous humour, or the ante-
rior furface of the cryftalline, by which the rays
cannot be brought into a focus upon the retina,
they can difcern in no other manner, than a found
eye can through a glafs of broken jelly, where a
great variety of furfaces fo differently refract the
light, that the feveral diflinct pencils of rays can-
not be collected bv the eye into their proper foci ;
wherefore fc the fhape of an object in fuch a cafe
cannot be at all difcerned, though the colour may :

.And

Or the EYE. 301

And thus it was with this young gentleman, who,
though he knew thefe colours afunder in a good
light, yet when he faw them after he was
couched, the faint ideas he had of them before,
were not fufficient for him to know them by after-
wards, and therefore he did not think them the
fame which he had before known by thofe names.
Now fcarlet he thought the moft beautiful of all
colours, and of others the moil gay were the moft
pleafmg ; whereas the firft time he faw black it
gave him great uneafinefs, yet after a little time he
was reconciled to it ; but feme months after, fee-
ing by accident a negro woman, he was (truck
with great horror at the fight.

When he firft faw, he was fo far from mak-
ing any judgment about diftances, that he thought
all objects whatever touched his eyes (as he ex-
preffed it) as what he felt did his fkin, and thought
no objects fo agreeable as thofe which were fmooth
and regular, though he could form no judgment
of their fhape, or guefs what it was in any object
that was pleafmg to him : He knew not the fhape
of any thing, nor any one thing from another,
however different in fhape or magnitude; but
upon being told what things were, whofe form
he before knew from feeling, he would carefully
obferve, that he might know them again ; but
having too many objects to learn at once, he for-
got many of them; and (as he faid)'at firft he
learned to know, and again forgot a thoufand

things

302 Or the EYE.

things in a day. One particular only, though it
may appear trifling, I will relate : Having often
forgot which was the cat, and which the dog, he
was aihamed to afk ; but catching the cat, which
he knew by feeling, he was obferved to look at
her ftedfaftly, and then, fetting her down, faid,
So, pufs, I fhall know you another time. He was
very much furprifed, that thofe things which he
had liked bell:, did not appear moft agreeable to
his eyes, expecling thofe perfons would appear
moil beautiful that he loved moft, and fuch things
to be moft agreeable to his fight that were fo to
his tafte. We thought he foon knew what pic-
tures reprefented, which were fhewed to him,
but we found afterwards we were miftaken ; for
about two months after he was couched, he dis-
covered at once they reprefented folid bodies,
when to that time he conlidered them only as
party-coloured planes, or furfaces diverfified with
variety of paint ; but even then he was no lefs
furprifed, expecling the pictures would feel like
the things they reprefented, and was amazed
"when he found thcfe parts, which by their light
and inadow appeared now round and uneven, felt
only flat like the reft, and afked which was the ly-
ing fenfe, feeling, or feeing ?

Being fhewn his father's picture in a locket
at his mother's watch, and told what it was, he
acknowledged a likenefs, but was vaftly furprifed ;
afking, how it could be, that a large face could

be

Of the EYE. 303

be exprefled in fo little room ; faying, it mould
have feemed as impoffible to him, as to put a
bufhel of any thing into a pint.

At firft, he could bear but very little light, and
the things he faw he thought extremely large ;
but upon feeing things larger, thofe firft feen he
conceived lefs, never being able to imagine any
lines beyond the bounds he faw ; the room he
was in, he faid, he knew to be but part of the
houfe, yet he could not conceive that the whole
houfe could look bigger. Before he was couched,
he expeded little advantage from feeing, worth
undergoing an operation for, except reading and
writing ; for he faid, he thought he could have
no more pleafure in walking abroad then he had
in the garden, which he could do fafely and read-
ily. And even blindnefs, he obferved, had this
advantage, that he could go any where in the dark,
much better than thofe who can fee ; and after
he had feen, he did not foon lofe this quality, nor
defire a light to go about the houfe in the night.
He faid, every new objed was a new delight ; and
the pleafure was fo great, that he wanted words to
exprefs it ; but his gratitude to his operator he
could not conceal, never feeing him for fome time
without tears of joy in his eyes, and other marks
of affedion : And if he did not happen to come
at any time when he was expeded, he would be
fo grieved, that he could not forbear crying at his
difappointment, A year after firft feeing, being

carried

304 Of the EAR.

carried upon Epfom Downs, and obferving a large
profpect, lie was exceedingly delighted with it,
and called it a new kind of feeing. And now
being lately couched of his other eye, he fays,
that objects at firft appeared large to this eye, but
not fo large as they did at firft to the other ; and
looking upon the fame object with both eyes, he
thought it looked about twice as large as with
the firft couched eye only, but not double, that
we can any ways difcover.

I have couched feveral others who were born
blind, whofe obfervations were of the fame kind ;
but they being younger, none of them gave fo
full an account as this gentleman.

. CHAP. V.
Of the Ear.

' 1 HE figure and fituation of the outer ear needs
no defcription. Its inner fubftance is cartilage,
which preferves its form without being liable
to break.. Its ufe is to collect founds, and direct
them into the meatus auditorius, which is the
paffage that leads to the drum ; this paffage is lined
with a glandular membrane, in which alfo is fome
hair ; the cerumen which is feparated by thefe
glands, being fpread all over this membrane, and
its hairs, ferve to defend the membrane from the

outer

Of the EAR. 305

outer air, and to entangle any infect that might
otherwife get into the ear. Sometimes this wax
being feparated in too great quantity, it fills up
the paffage and caufes deafnefs ; and thofe great
difcharges of matter from the meatus auditorius,
which are commonly called impofthumes in the
ear, I think, can be nothing elfe but ulcerations, or
great fecretions from thefe glands. At the farther
end of the meatus auditorius lies the membrana tym-
pani, which is extended upon a bony ridge almoft
circular. Its fituation in men and brutes is nearly
horizontal, inclined towards the meatus auditorius,
which is the beft pofition to receive founds ; a great
part of them being ordinarily reverberated from
the earth. In men and brutes it is concave out-
ward, but in birds it is convex outward, fo as to
make the upper fide of it nearly perpendicular to
the horizon, which feems fitter to hear' each other's
founds when they are high in the air, where they
can receive but little reverberated found. This
membrane does not entirely clofe the paffage, but
has on one fide a fmall aperture covered with a
valve. I found it once half open in a man that I
differed, who had not been deaf ; and I have ken
a man fmoak a whole pipe of tobacco out through
his ears, which muft go from the mouth through
the euitachian tube, and through the tympanum ;
yet this man heard perfectly well. Thefe cafes oc-
cafioned me to break the tympanum in both ears
of a dog, and it did not deftroy his hearing, but for

fome

306 Of the EAR.

fome time he received ftrong founds with groat
horror. Mr. St. Andre has aifured me, that a
patient of his had the tympanum deftroyed by an
ulcer, and the auditory bones caft out, without de-
ftroying his hearing. From thefe, and other like
cafes, it may be concluded, that the membrana tym-
pani, though ufeful in hearing, is not the feat of
that fenfe ; and if any difeafe in that membrane
mould obftrucl the pafTage of founds to the inter-
nal parts of the ear, which are the feat of that
fenfe, an artificial paifage through that membrane
might recover hearing, as the removing the cryftal-
line humour, when that obftrucls the light, recov-
ers fight. Some years Stsce a malefactor was par-
doned on condition that he fuffered this experiment,
but he falling ill of a fever, the operation was de-
ferred, during which time there was fo great a
public clamour raifed againft it that it was afterwards
thought fit to be forbid. In very young children
I have always found this membrane covered with
mucus, which feems neceifary to prevent founds
from affecting them too much, there being no pro-
vifion to fhut the ears, as there is for the eyes. A
gentleman well known in this city, having had
four children born deaf, was advifed to lay blifters
upon the heads of the next children he might have,
which he did to three which were born afterward,
and every one of them heard well. It feems not
unreafonable to fuppofe that too great a quantity of
this mucus upon the drum might be the caufe of

deafnefs

Of the Ex\R. 307

deafnefs in the four children, and that the difcharge
made by the blifters in the latter cafes was the caufe
of their efcaping the fame misfortune.

• Into the middle of the tympanum is extended
a fmall bone called malleus, whofe other end is
articulated to a bone called incus, which is alfo .ar-
ticulated by the intervention of an exceeding fmall
one, called orbicuiare, to a fourth bone called fta-
pes. * Thefe bones are contained in that cavity be-
hind the tympanum, which is called the barrel of
the ear ; but fome anatomifts call the barrel only
tympanum, and the membrane membrana tympa-
ni. The malleus being moved inward by the muf-
culus obliquus internus, or trochlearis, it extends
the tympanum that it may be the more affected by
impulfe of founds when they are too weak. This
mufcle rifes from the cartilaginous part of the eu-
ftachian tube, and paffing from thence in a proper
groove, it is reflected under a fmall procefs, and
thence paifes on perpendicular to the tympanum,
to be inferted into the handle of the malleus,
fometimes with a double tendon. Parallel to this
mufcle lies another extenfor of the tympanum,
called obliquus externus ; it arifes from the outer
and upper part of the euftachian tube, and paffing
through the fame hole with the chorda tympani,
which is a branch of the fifth pair of nerves, it is
inferted into a long procefs of the malleus : This
is not fo obvioully an extenfor as to be known
to be fo without an experiment. The mufcle

which

308 Of the EAR.

which • relaxes this membrane is called externus
tympani ; it arifes from the upper part of the au-
ditory paffage, under the membrane which lines
that paffage, and is inferted into the upper procefs
of the malleus. The relaxation of the tympanum
is made by this mufcle, without our knowledge,
when founds are too ftrong ; and as the pupil of
the eye is contracted when we have too much
light, and dilated when there is too little, from
what caufe foever, fo when founds are too low,
or the fenfe of hearing imperfect, from whatever
caufe, the extenfors of the tympanum ftretch it to
make the impulfe of founds more effectual upon
it, juft as in the cafe of the common drum, and
the chofds of any mufical inftrument. From the
cavity behind the tympanum, which is called the
barrel of the ear, goes the euftachian tube, or
iter ad palatum ; it ends cartilaginous behind the
palate. This paffage feems to be exactly of the
fame ufe with the hole in the fide of the common
drum, that is, to let the air pafs in and out from
the barrel of the ear to make the membrane vibrate
the better, and perhaps in the ear, which is clofer
than a common drum, to let air in or out as it
alters in denfity ; and if any fluid mould be fepa-
rated in the barrel of the ear, to give it a paffage
out. This paffage being obftructed, as it is fome-
times, by a large polypus behind the uvula, it
eaufes great difficulty of hearing, and fometimes,
when the meatus auditorius is obftructed, a man

opening

Of the EAR. 309

opening his mouth wide, will hear pretty well
through this paflage, which is often fo open, as
that fyringing water through the nofe, it Ihall pafs
through into the barrel of the ear, and caufe deaf-
nefs for fome time. If any one would try how
he can hear this way, let him ftop his ears, and
take between his teeth the end of a wire, or chord
that will vibrate well, and holding the other end,
ftrike it, and the found that he hears will be
through this pafTage. To the ftapes there is one
mufcie, called mufculus ftapedis ; it lies in a long
channel, and ending in the ftapes, it ferves to pull
the ftapes off of the feneftra ovalis, which other-
wife it covers. Befides the feneftra ovalis, there
is another near it, fomewhat lefs, called rotunda ;
thefe two holes lead to a cavity called veftibulum,
which leads into other cavities aptly called cochlea,
and three fernicircular canals, or all together the
labyrinth, in which are fpread the auditory nerves,
to receive and convey the impulfe of founds to
the common fenforium the brain ; and furely the
chorda tympani, which is a branch of the fifth
pair of nerves, may alfo convey thefe fenfations
to the brain. The two holes, called feneftra ovalis
and rotunda, are clofed with a fine membrane, like
the membrane called the drum, and the larger
being occafionally covered and uncovered by the
ftapes, founds are thereby made to influence more
or leis, as bell ferves for hearing ; and this advan-
tage being added to that of a lax or tenfe tympa-
num,

3 io SENSES of SMELLING,

num, the effecT: of founds may be greatly increafed
or leifened upon the auditory nerves, expanded in
the labyrinth. In the ftrongeft founds, the tympa-
num may be lax, and the feneftra ovalis covered ;
and for the loweft, the tympanum tenfe and the
feneftra uncovered. If founds propagated in the
ear were heard lefs, we might often be in danger
before we were apprized of it ; and if the organs of
hearing were much more perfect, unlefs our un-
derftandings were fo too, we mould commonly hear
more things at once than we could attend to.

C H A P. VI.

Of the Senses of Smelling, Tasting, and
Feeling.

THE fenfe of fmelling is made by the effluvia,
which are conveyed by the air to the nerves,
ending in the membranes which line the nofe and
its lamella.-. In men thefe lamella? are few, and
the paffage through the nofe not difficult ; hence
fewer effluvia will ftrike the nerves, than in ani-
mals of more exquifite fmell, whofe nofes being
full of lamellae, and the paffage for the air narrow
and crooked, few of the effluvia efcape one place
or another ; befides, their olfactory nerves may be
more fenfible. Fifh, though they have no nofes,
yet in their mouths they may tafte effluvia in the
water, as furely thofe fifh do, who feek their prey

in

TASTING, and FEELING. 311

in the darkeft nights, and in great depths of water,
there being more nerves difpofed in their mouths
than through their whole bodies befide, the optic
excepted ; and it feems as if it was done for this
purpofe ; for the mere fenfe of tailing is ordinari-'
ly lefs curious in them than in land animals ;
in baiting eel-bafkets, if the bait has lain long in
water, it is feldom followed ; but upon fcarifying
it afrefh, which will make it emit new effluvia,
it ferves as a frefh bait. The fenfe of tailing is
made in the like manner upon the nerves which
line the mouth, as is that of feeling upon the nerves
diftributed throughout the body ; of which I mould
fpeak more in this place, if I had not done it al-
ready in the chapter of the nerves.

TAB.

( 3 12 )

TAB. XXXI.

i The under fide of the bladder.

2 The ureters.

3 Vafa deferentia.

4 Veficulae feminales.

5 The proftate gland.

6 Meatus urinarius.

7 A tranfverfe fec>ion of the corpora cavernofa

penis.

8 Corpus cavernofum urethra?.

9 Urethra.

io Septum penis.

1 1 The feptum between the corpus cavernofum

urethra?, and that of the penis.

12 The corpora cavernofa penis divided by the

feptum.

13 Corpus cavernofum glandis.

TAB.

TAB. XXXI

J>3

13,.

II

TAB. XXXII.

V.31S.

( 3*3 )

TAB. XXXII.

1 That fide of the uterus which is next the gut.

2 The fallopian tubes.

3 The fimbriae.

4 Ovaria.

5 The mouth of the uterujp.

6 Ligamenta rotunda.

7 The infide of the vagina.

8 The orifice of the meatus urinarius.

9 The glans clitoridis.

io The external labia of the vagina.
1 1 The nymphae, which are continued from the
prxputium clitoridis.

W TAB.

( 3*4 )

TAB. XXXIII.

The parts of an hermaphrodite negro, which was

neither fex perfect, but a wonderful mixture of

both. This perfoh was twenty-fix years of

age, and in fhape perfectly male.

i A clitoris, when erected, almoft as large as a

penis.

2 The glands of the clitoris.

3 Labia, or a divided fcrotum ; in which were

perfect tefticles with all the veflels.

4 Nymphse.

5 The entrance into the vagina, where were

carunculse myrtiformes.

6 Furca virginis.

The lower figure reprefents another her-
maphrodite, whofe fhape was rather female
than male, but too young to have female
breafts, or a beard, like a male, upon the
face.

7 The glans clitoridis.

8 Nymphse.

9 Labia with tefticles in them, divaricated to

mew the parts between, but in their natural
fituation very like the other, as the other
when divaricated refembled this.

I o The entrance into the vagina.

I I Furca virginis.

TAB.

TAB. XXXI II

TAB . XXXIV

( 3i5 )

TAB. XXXIV.

i The right ventricle of a foetus diftended with
wax.

2 The right auricle.

3 The left auricle.

4 Branches of the pulmonary veins of the right

lobe of the lungs, thofe of the left being cut
off fhort.

5 The arteries of the left lobe of the lungs.

6 The vena cava defcendens.

7 Aorta afcendens.

8 Arteria pulmonalis.

9 Ductus arteriofus.

io The under fide of a heart of a younger foetus.

1 1 The right auricle cut open.

1 2 The cava defcendens cut open.

13 Tuberculum Loweri.

14 The foramen ovale clofed with its valve.

1 5 The mouth of the coronary veins.

16 The umbilical vein.

1 7 Branches of the vena porta in the liver.

18 Du&us venoms.

19 Branches of the cava in the liver.

20 Vena cava.

\V 2 TAB,

( 3*6 )

TAB. XXXV.

i A crofs for an object.

2 The object reprefented on the retina at the

bottom of each eye.

3 The entrance of the optic nerves, in which

place no object is reprefented.

4 Cones, within which all objects placed are dark

to each eye, the rays from thence falling upon
the entrance of the optic nerves ; but that
which falls upon the entrance of the optic
nerve in one eye, can never fall upon the optic
nerve in the other.

5 Pencils of rays from points of the object paffing

through the cryftalline humour, where they
converge, to meet in a point on the retina to
form vifion.

TAB.

TAP. XXXV.

P. j.i 6.

Jiniliiiilguiullui.iiiiiuuuiu il»IIIIIIIIIIIIINmillii.i.iiiiiiii iiiii milium ijiimnui, immm il iiiillli . 'i . u,L, !i . I uii ii ll ll l lll llllUI I IIII III I IIIIIIIIII ' ll l llll l l i mik

i\ 5

■

■

1 1 •.

i ■ '■

y /v

\\k|

//.'

tf

TAB XXXVI

/'../;

( 317 )

T A B. XXXVI.

i A knife palTed through the tunica fclerotis, mi-
tier the cornea before the iris, in order to cut
an artificial pupil where the natural one is
clofed. This operation I have performed
feveral times, with good fuccefs ; indeed it
cannot fail when the operation is well done,
and the eye no otherwife difeafed, which is
more than can be faid for couching a cataract.
In this operation great care muft be taken to
hold open the eye-lids without prefling upon
the eye, for if the aqueous humour is fqueez-
ed out before the incifion is made in the iris,
the eye grows flaccid, and renders the opera-
tion difficult.

2 A crooked needle pafTed through a proptofis
of the cornea ; the black line in the cornea
inclofes the piece to be cut out with a knife.
The operation being thus done, the cryftal-
line humour immediately falls out ; and in a
few days the lips of the wound unite. This
operation is very ufeful, and attended with
but little pain. I have done the fame thing
when the whole eye has been fo enlarged
that the eye-lids could not be clofed, which
has funk the eye in the head ; but this ope-
ration was attended with fuch violent pain
that I cannot much recommend it.

3 Shews

( 3«8 )

3 Shews how an opaque fear upon the cornea,

by obftru&ing part of each pencil of rays,
makes a dimnefs of fight without a total lofs,

4 Shews how a cataraft or obftru&ion of the

cryftalline humour will obftrucT: the light
which is before it. And how fome fide-
light may pafs* to the retina through the
aqueous humour, but not being brought into
a focus gives only a fenfe of light without
vifion.

TAB.

TAB.XXXVTTT.

J>J21

r.\r>.x xwii.

( 3*9 )

T A B. XXXVII.

? A bone taken out from the firft procefs of the
dura mater not far from the crifta galli.

2 A bone taken out of the mufcular part of the

heart of a man.

3 The under fide of a bone taken out of a frac-

tured fcull.

4 The upper fide of a bone from the fame fcull,
where the operation of the trepan had been
thrice made. This girl was brought into the
hofpital a week after the accident. I im-
mediately opened the fcalp, and let out about
two ounces of grumous blood, and laid the
fcull bare about four inches one way, and
three the other, and tied the blood vefTels,
that I might make the operation without
much difficulty foon after. The fracture
extended acrofs the os bregmatis from the
fagittal future to the temporal bone ; that
part next the os frontis was depreffed equal
to its thicknefs, and a great deal of extrava-
fated blood, and fome matter, lay under the
other part of the fame bone. I made two
perforations with the trephine, clofe to the
fracture, that I might raife it up fteadily
through both, and have more room for the
extravafated blood to difcharge from under
the fcull, which had difcharged before in

great

( 3 2 ° )

great quantity through the fracture. But
neverthelefs, ten days after the former opera-
tion, I was obliged to make another perfora-
tion to difcharge the matter more freely ; for,
during a month, the matter ran through all
her dreffings down her face twice every day,
and was exceedingly fetid, and for the fpace
of three months the matter decreafed very
little in quantity, but grew lefs and lefs of-
fenfive. September the thirteenth, the leaft
of the bones was taken out ; and on Sep-
tember the twenty-ninth, the large one;
after which time the matter was good, and
not too much in quantity. Each of thefe
bones is through both tables, for the motion
in the brain was feen, only fome little parts
of the lefTer bone remaining, a callus was
formed from them ; but where the great one
came away there was no callus, only a com-
mon cicatrix ; and befides thefe, many little
bits of bone came away in the dreflings : She
was foon after cured, and has remained well
many years.

T A B.

'VCr-

21

TAB. XXXVIII.

The figure of Samuel Wood, a miller, whofe
arm with the fcapula was torn off from his
body, by a rope winding round it, the other
end being fattened to the coggs of a mill.
This happened in the year 1737. The veflels
being thus ftretched bled very little, the arte-
ries and nerves were drawn out of the arm ;
the furgeon who was firft called placed them
within the wound, and drefled it fuperficially.
The next day he was put under Mr. Ferne's
care, at St. Thomas's hofpital, but he did not
remove the dreflings for fome days. The pa-
tient had no fevere fymptoms, and the wound
was cured by fuperficial dreflings only, the nat-
ural fkin being left almoft fufficient to cover
it ; which fhould in all cafes be done as much as
may be. About twenty years fince, I introduced
the method of amputating, by firft dividing the
fkin and membrana adipofa, lower than the place
where the operation was to be finifhed, the ad-
vantages of which are now fufnciently known.

1 The end of the clavicle,

2 The cicatrix.

3 The fubfcapularis mufcle.

4 The cubit broke in two places.

TAB.

( 3 22 )

TAB. XXXIX.

Reprefents the cafe of John Heysham, who,
the Friday before Eaiter, in the year 1721, by
overftraining himfelf at work, had a rupture
of the inteftines into the fcrotum, which could
by no means be reduced. He was brought
into St. Thomas's hofpital the Monday follow-
ing, and I would have performed the operation
immediately, but he refufing to fubmit, it was
deferred till Tuefday morning, when, he be-
ing willing, I performed the operation, and
making a large wound in the bottom of the
abdomen, the inteftines were eahly reduced,
and near a quart of water was difcharged out
of the fcrotum at the fame time. There had
been a rupture of the omentum before, which
being united to the fcrotum and fpermatic vef-
fels, I palled a needle with a double ligature
(as is exprefled in the plate) under that part
of the omentum that adhered, fo as not to
hurt the fpermatic veffels ; then cutting out
the needle, I tied one of the firings over the
upper part of the omentum, and the other
over the lower, and then cut off as much of
it as was in the way. My reafon for tying in
this manner was to fecure the blood veffels,
which, I think, could not be done fo well
with one ligature, becaufe of the largenefs of

the

TAB. XXXIX.

F.39,%

TAB. XL.

V <l*4-

V

c

( zn )

the adhefion and the texture of the omentum,
which renders it too liable to be torn by fuch
a bandage. Three days after the operation an
eryfipelas began in his legs, and fpread all over
his body, the cuticle every where peeling off;
yet he recovered, and continues in a good ftate
of health. After he was cured, at firft he wore
a fmall trufs, but left it off in a ftiort time,
and now feels no inconvenience from it, though
he lives by hard labour.

TAB.

( 3 2 4 )

TAB. XL.

The cai Margaret White, the wife of

Joi uite, ii penfioner in the Fifhmongers

*es at Newington in Surry. In the

ear of her age, fhe had a rupture at

hei 1, which continued till her feventy-

third year, when, after a fit of the cholic, it

rtified, and fhe being prefently after taken

with a x'-omiting, it burft. I went to her, and

found her in this condition, with about fix and

:;nty inches and a half of the gut hanging

d. I took away what was morti-

he end of the found gut hanging

1, to which it afterwards ad-

-cd, and lived many years

crements through the in-

avel ; and though the ulcer was

: on feparated, that

feen ; yet they

at the wound,

bed, and fat up

CHAP.

( 3*5 >

CHAP. VI.

A short Historical Account of Cut-
ting for the Stone.

I HE moft ancient way of cutting for the
ftone is that defcribed by Celsus, which
was indeed cutting upon the gripe, but in a very
different manner from that operation in later agts,
for he direds a lunated incifion with the horns
towards the coccyges, which was plainly that the
gut might be prefled downwards to avoid wound-
ing it, and then a tranfverfe incifion upon the
ftone might be made fafely, but not in very young
children, for want of room, nor after puberty,
for then the proftatse are too large to allow of
this operation ; therefore they did not ufually cut
any younger than nine years, nor older than four-
teen. Afterwards, but when we know not, this
operation was improved by cutting lower, and on
one fide, which is the operation now called cutting
on the gripe, or with the leffer apparatus.

In the year 1524, Marianus publifhed the
method of cutting by the greater apparatus, now
commonly called the old way, but he owns it was
invented by his mafter Johannes de Romanis.

In the year 1697, Frere Jacques came to
Paris, full of reputation for the fuccefs of his new
operation for the ftone ; he foon obtained leave to
cut in the hofpitals, where great numbers of his

patients

326 CUTTING for the STONE.

patients dying, and Being difTe&ed, they were
found with their bladders cut through, guts
wounded, &c. which brought the operation into
difgrace, as Mery and Dionis have related, who
faw thefe things. They fay he performed the ope-
ration without any direction, and without any
knowledge of the parts he was to cut ; a thing not
to be mentioned without horror ! But of late his
character has been fet in a very different light ;
and though it is more than probable he himfelf
knew not what he did, yet there are now, who pre-
tend to tell us exactly ; though if their teflimonies
are to be regarded, who faw him operate, there is
no place that he did not cut one time or other, and
therefore he may have a fort of right. to be called
the inventor of any operation for the ftone that can
ever be performed in thefe parts. It is alfo owned
that he fometimes had great fuccefs, which was
enough to put others of that nation upon trying of
it in a more judicious manner ; but if there were
fuch, failing of fuccefs r they have concealed their
experiments.

Mr. Rau of Amfterdam, who faw F. Jacques
operate, profeifed to do his operation with the
neceflary improvement c: a grooved ftaff, which if
Jacques ever ufed, he furely learned that of
Rau. He fucceeded wonderfully ; and if he, who
was an excellent anatomift, may be allowed to
underftand his own operation, it was directly into
the bladder, without wounding either the urethra

or

CUTTING for the STONE. 327

or the proftates : befides this, other competent
judges, who were witneffes to his operations, have
bore the fame teftimony.

In the year 171 7-1 8, Doctor James Doug-
lass, in a paper prefented to the Royal Society,
demonftrated from the anatomy of the parts, that
the high operation for the ftone might be prac-
tifed ; which had been once performed by Franco
injudicioufly, and by him difrecommended, though
his patient recovered ; and afterwards ftrongly
recommended, but not praclifed by Rosset. Yet
no one undertook it, till his brother, Mr. John
Douglass, about three years after, performed it,
and with great applaufe, his two firft patients re-
covering. Soon after, a furgeon of St. Thomas's
hofpital cut two, who both recovered ; but the
fame gentleman afterwards cutting two, who mif-
carried by the cutting or burfting of the peritonae-
um, fo that the guts appeared, this way imme-
diately became as much decried as it was before
commended ; upon which the furgeons of St. Bar-
tholomew's hofpital, who had prepared to perform
this operation, altered their refolution, and went
on in the old way. The next feafon, it being my
turn in St. Thomas's, I refumed the high way,
and cutting nine with fuccefs, it came again in
vogue ; after that every lithotomift of both hof-
pitals pra&ifed it ; but the peritonaeum being
often cut or burft twice in my practice, though
fome of thefe recovered, and fometimes the

bladder

328 CUTTING for the STONE.

bladder kfelf was burft, from injecting too much
water, which generally proved fatal in a day or
two. Another inconvenience attended every ope-
ration of this kind-, which was, that the urine's
lying continually in the wound retarded the cure,
but then it was never followed with an inconti-
nence of urine. What the fuccefs of the feveral
operators was, I will not take the liberty to pub-
lifh ; but for my own, exclufive of the two before
mentioned, I loft no more than one in feven,
which is more than any one elfe that I know of
could fay ; whereas in the old way, even at Paris,
from a fair calculation of above 800 patients, it
appears that near two in five died. And though
this operation came into univerfal difcredit, I muft
declare it my opinion, that it is much better than
the old way, to which they all returned, except
myfelf, who would not have left the high way
but for the hopes I had of a better ; being well
aifured, that it might hereafter be practifed with
greater fuccefs ; thefe fatal accidents having pret-
ty well fhewn how much water might be inject-
ed, and how large the wound might fafely be
made. But hearing of the great fuccefs of Mr.
Rau, profeflbr of anatomy at Leyden, I deter-
mined to try, though not in his manner, to cut
directly into the bladder ; and as his operation was
an improvement of Friar Jacques, I endeavoured
to improve upon him, by filling the bladder, as
Douglass had done in the high way, with water,

leaving

CUTTING for the STONE. 329

leaving the catheter in, and then cutting on the
outfide of the catheter into the bladder, in the
fame place as upon the gripe, which I could do
very readily, and take out a ftone of any fize with
more eafe than in any other way. My patients,
for fome days after the operation, feemed out of
danger ; but the urine which came out of the
bladder continually lodging upon the cellular
membrane on the outfide of the re&um, made
foetid ulcers, attended with a vaft difcharge of
ftinking matter ; and from this caufe I loft four
patients out of ten. The cafe of one which efcaped
was very remarkable ; a few days after he was
cut, he was feized with a great pain in his back
and legs, with very little power to move them ;
upon which he turned upon his face, and refted
almoft conftantly upon his knees and elbows above
a fortnight together, having no eafe in any other
pofture all that while ; at length his urine coming
all the right way, his wound foon healed, and he
recovered the ufe of his back and limbs. I think
all thefe fevere fymptoms could proceed from no
other caufe than the urine and matter fomehow
offending the great nerves ; which come out of
the os facrum to go to the lower limbs. I then
tried to cut into the bladder, in the fame manner
that Mr. Rau was commonly reported to do, but
there had the fame inconvenience from the urine's
lodging upon the cellular membrane on the out-
fide of the inteftinum rectum. Upon thefe dif-
X appointments,

j3o CUTTING for the STONE.

appointments, I contrived the manner of cuttings
which is now called the lateral way. This ope-
ration I do in the following manner : I tie the
patient as for the greater apparatus, but lay him;
upon a blanket feveral doubles upon an horizontal
table three foot high, with his head only raifed.
I firft make as long an incifion as I can, beginning
near the place where the old operation ends, and
cutting down between the mufculus' accelerator
urinse, and erector penis, and by the fide of the
mteftinum rectum : I then feel for the ftafF,
holding down the gut all' the while with one or
two fingers of my left hand, and cut upon it in
that part of the urethra which lies beyond the
corpora cavernofa urethras, and in the proftate
gland, cutting from below upwards, to avoid
wounding the gut ; and then paffing the gorget
very carefully in the groove of the ftafF into the
bladder, bear the point of the gorget hard againft
the ftafi^ obferving all the while that they do
not feparate, and let the gorget flip to the out-
fide of the bladder ; then I pafs the forceps into
the right fide of the bladder, the wound being
on the left fide of the perinaeum ; and as they
pafs, carefully attend to their entering the blad-
der, which is known by their overcoming a ftrait-
nefs which there will be in the place of the wound ;
then taking care to pufh them no farther, that
the bladder may not be hurt, I firft feel for the
ftone with the end of them, which having felt,

I open

CUTTING for the STONE. 331

I open the forceps and Aide one blade underneath
it, and the other at top ; and if I apprehend the
ftone is nqt in the right place of the forceps, I
fhift it before I offer to extract, and then extract
it very ^deliberately, that it may not flip fuddenly
out of the forceps, and that the parts of the
wound may have time to ftretch, taking great
care not to gripe it fo hard as to break it, and if
I find the ftone very large, I again cut upon it as
it is held in the forceps. Here I muft take notice,
it is very convenient to have the bladder empty
of urine before the operation, for, if there is any
quantity to flow out of the bladder at the paffing
in of the gorget, the bladder does not contract
but collapfe into folds, which makes it difficult to
lay hold of the ftone without hurting the blad-
der ; but if the bladder is contracted, it is fo eafy
to lay hold of it, that I have never been delayed
one moment, unlefs the ftone was very fmall.
Laftly, I tie the blood veffels by the help of a
crooked needle, and ufe no other dreffing than a
little bit of lint befmeared with blood, that it may
not ftick too long in the wound, and all the dreffc-
ings during the cure are very flight, almbft fuper-
ficial, and without any bandage to retain them ;
becaufe that will be wetted with urine, and gall
the fkin. At firft I keep the patient very cool to
prevent bleeding, and fometimes apply a rag dipt
in cold water, to the wound, and to the genital
parts, which I /iave found very ufeful in hct
X 2 weather

$$2 CUTTING for the STONE.

-weather particularly. In children it is often alone
fumcient to ftop the bleeding, and always helpful
nen. The day before the operaf VV * g* lve a
p-^rge to empty the guts, and never ^ ] e& to
give forne laxative medicine or clyfter a '. ' days
after, if the belly is at all tenfe, or if tl ivc

not a natural ftool. What moved me to try this
way, if I may be allowed to know my own'
thoughts, was the consideration of women fcarce
ever dying of this operation ; from which I con-
led, that if I could cut into- the urethra, beyond
corpora cavernofa urethras, the operation 1
would be nearly as fafe in men as women.

What fuccefs I have had in my private practice
I have kept no account of, becaufe I had no in-
tention to publiih it, that not being fufficiently wit-
neiTed. Publickly in St. Thomas's hofpital I have
cut two hundred and thirteen ; of the firft fifty,
only three died j of the fecond fifty, three ; of the
third fifty, eight ; and of the laft fixty-three, fix.
Several of thefe patients had the fmall-pox during
their cure, fome of whom died, but I think not
more in proportion than what ufually die of that
diftemper ; thefe are not reckoned among thofe
who died of the operation. The reafon why fo
few died in the two firft fifties was, at that time
few very bad cafes offered ; in the third, the ope-
ration being in high requeft, even the raoft aged
and mod miferabie cafes expected to be faved by
it ; beiides, at that time, I made the operation

lower,

CUTTING for the STONE. 333

lower, in hopes of improving it, but found I
was miftaken. But what is of mod confe-
rence to be known is the ages of thofe who re-
covered, and thofe who died. Of thefe, under
ten years of age one hundred and five were cut,
three died; between ten and twenty, fixty-two
cut, four died ; twenty and thirty, twelve cut,
three died ; thirty and forty, ten cut, two died ;
forty and fifty, ten cut, two died.; fifty and
fixty, feven cut, four died ; fixty and feventy,
five cut, one died ; between feventy and eighty,
two cut, one died. Of thofe who recovered the
three biggeft ftones were % xii, x~, and viii, and
the greateft number of ftones in any one perfon
was thirty-three. One of the three that died out
of the hundred and five, was very ill with a
whooping-cough ; another bled to death by an
artery into the bladder, it being very hot weather
at that time : But this accident taught me after-
wards, whenever a veffel bled that I could not
find, to dilate the wound with a knife, till I
t could fee it. Now if Jacques or others, who
of late have been faid to have performed this
operation, whether by defign or chance, did not
take care to fecure the blood veffels, which as
yet has not been fuppofed, whatever their dexter-
ity in operating might be, their fuccefs at Ieaft
can be no fecret, for many of their children and
moil of their men patients mull have bled to
death. If I have any reputation in this way,

I havq

334 CUTTING for the STONE.

I have earned it dearly, for no one ever endured more
anxiety and ficknefs before an operation, yet from
the time I began to operate, all uneafinefs ceafed ;
and if I have had better fuccefs than fome others,
I do not impute it to more knowledge, but to the
happinefs of a mind that was never ruffled or dis-
concerted, and a hand that never trembled during
any operation.

INDEX.

N D E X.

ADIPOSE membrane - - 137

■ - its difeafes - 138

Alantois - - - - - - 280

Amnion - - - - - - - 278

> does its liquor ferve as nourifhment ?

Amputation, how is the circulation kept up after

it ? ...--- 203
occafioned, and proving fatal from the

cramp 207

in mortifications ought to fucceed the

feparation - - - - * •- 208

Anafarca - - - - • - 13

AnchylofiS) how formed - 8

Aneurifm - l8 7
Animal body, what

j

its conftituent parts - 2
Animals, why larger have flower pulfes, and lefs

vigour in motion »-''»;- 200

why inactive ones require lefs food, and

are not fo fuddenly deftroyed by wounds 207
Antra. Vide Sinus maxilla fup.

Aorta, frequently offified near the heart - 182
• its valves covered with chalk - - 182

preternaturally diftended - - 182

traced l8 3

Aqueous humour of the eye - - 296

Arm, right, why more ufed than the left - 24

Artery, coronary - I <H

carotids, why rifing differently - - 184

Artery,

336 I N D E X.

Page

Artery, cervical - - - - - 186

fubclavian, axillaiy, &c. - - 186

intercoftal, &c. - - - - 188

phrenic, &c, - - - - 188

iliac - - - - - - 189

inguinal, &c. - - - - 19°

■ pulmonary - - - - - 183

Arteries, what " * ' - «■ « 2

* become bony - 5

coats - - * " m • 194* 20 °

• the angles and laws of ramification - 195

the force of their contractions - - 196

motion of the blood in them and in the

veins 199, &c.

Arachnoides of the brain - - - - 221

Atlas, ovfirji vertebra - - - - 22

Barrennefs of women - 276

Bile, in what quantity - - - - 164

- concreting, forms ftones « * - 166

Biliary duels -■ 163

. obftructed * - - 166

Bladder of urine ----- 260

■ feldom ulcerated - - - - 261

Blood, quantity, celerity of its motion, &c. 206

extravafated, requires firlt purging, and

then warm attenuant - 208

Blood-letting 89

what artery in danger - - - 187

Bones, what -,---- 3

■ ufe - 4

fibres - - - - - -4, 9

how offify and grow - 4

fometimes decreafe or wafte - 5

why hollow ----- 6

their place fupplied by (hells in fmall animals 7

broken, how united by the callus - 7

have not vifible lamella - 9

1- their compact and fpongy fubftance - 9

Bones,

INDEX. 337

Page

Bones, diftorted or fractured, cured by an indu-
rating pafte - - - - 37
* their difeafes, particularly caries - 38

of the cranium - - - - n

trunk - * r - - 21

upper limb - 29

lower limb ^ 34

•< internal ear - 307

Bony excrefcences - 5
Brain - - - - * - - 222
full of water in a lethargy - - 224

its ftate in an apoplexy - 224

fchirrhous humours in the cerebrum - 225

impofthumations of the cerebrum 225

Breaft and its cancer - * t -* 140

Cacum* or appendix vermiformis - - 156

Callus* unites fractured bones - 7

Canalis arteriosus - - - - - 2 °4

Cancer ' ------ 140

Caries of bones - - - - - 39

Carpus* bones of ,. - - - - 32

Cartilages, what - 3

_ fubjed to offification «• 5

fwelled in rickets «• 5

prevent contiguous moveable bones from

uniting - ^

eroded, occafion anchylofis * °

where placed and ufe - - 41, &c.

moveable in the joint of the jaw 4 1

femilunar in the knee - 4^

Cartilago erjiformis «■ 2 °

Caruncula lachrymalis - 2 9 r

CaruncuU myrtiformes - 2 73

urethra - 2 °°

Caftration, how to fecure the veffels - 265

Qatamenia - " 2 7S

Cataract,

338 INDEX.

Page

Cataract, why the patient does not difcern objects,

though fenfible of light and colours - 300
Cerebellum .- - * r - - - 223

. its wounds caufe fudden death - 224

Cerebrum ------- 222

. its wounds not mortal * 224

Chorion ------- 2,78

Choroides oculi - - - - - - 293

Circulation, the complete revolution - r 217

in fmall veflels, and in living animals 204

Clavicula - - - - - - - 29

Clitoris 272

Colon - - - - - - - 156

Conception ----- 269, 276

Conjunctiva oculi ■• - - - - - 291

Cornea oculi - - - - - - 291

— a great refractor of light - r 298

Couching, not fo much refraction in the eye after

the operation - - - - - 298

. hiftoryof a young gentleman - - 300

Cowper, Mr. his operation on the antrum - 19

Cramp, occafioning firft amputation, and then death 207
Cranium, why compofed of feveral bones - 12

Cryftalline humour - - - - - 297

a lens for refraction 297, 298, 299

Cuticula - - - - ■ - - - 134

— — — its difeafes . - - - - - 134
Cutis - - - - - - - 135

fmall painful tumors under it - - 136

Chylification - - - - - - 216

Deafnefs caufed by redundant cerumen - - 305
in fome cafes, perhaps, might be cured by per-
forating the membrana tympani - 306

■ ■ in three cafes, probably, prevented by blifter-

ing immediately after birth - - 306

cauled by the polypus of the nofe comprefling

the Euftachian tube - 308

Denies.

INDEX. 339

Dentes. Vide Teeth.

Digeftion of the aliment - 152, 216

Diflocation of the thigh r 44

: — knee ----- 45

Dropfy and tapping - - - r - 211

• of the liver - - - - - 212

true af cites never cured - - - 215

? in the duplicature of the peritoneum 148, 149

Duclus arteriofus - - - - - 284

1 how clofed - - t - 287

thoracicus - - - - - 169

venofus ------ 283

Duodenum - - * - - - 155

Dura mater - - - - - - 218

; . ' its finufes - - - - - 219

! oflified - 221, 319

Ear, external - - - - - - 304

impofthumes of - - - - - 305

— — membrana tympani - - - - 30^

naturally perforated - 305

■ broke in a dog, without caus-
ing deafnefs - 305

*— deftroyed by ulcer, and the

fmall bones thrown out, with-
out deafnefs - 305

** — — . — its perforation propofed - 306

fmall bones, with mufcles of the malleus - 307

Euftachian tube - 308

Jiapes with its mufcle - 309

labyrinth - - - - - - 309

Emphyfema -- - - - - 138

Epididymis - r - * - - 265

Epiphyjis of bones " 8

Epigqjlrium - - - - - - 234

Erection of the penis - - - - 269

Excretory vefTel ------ 3

Exfoliation of bones - - - #" 39, 40

Extravafation. Vide Blood.

Eye

34* INDEX.

Pa

Eye 2 9°

— tunica conjunctiva 291

fclerctis et cornea - - - - 291

. — iris procejus ciliares - - - - 2 9*

— tunica cboroides -- - - - 293
— retina - - - - - - 293

— humours of 296

inflammations of, require immediate affift-

ance • - - - 2 99

— membrana niclitans, in amphibious animals, not

for refraction 2 97

Feeling, the fenfe of 3 11

Females, why fewer born than males - - 275

Fibres what .----- 2

Fibula ....--- 36
Figures of the bones.

1 . The fkeleton of a child twenty months old ^
The thigh-bone of a man fawed through > 50
The os bregmatis of a foetus of fix months j

2. The head with the lower jaw - - 51

3. A fe&ion of the fcull and upper jaw "\
The os fphemider - - - V 52
The infide of the bafe of the fcull J

4. The trunk - - -/ ;- - 53

5. The vertebra - - - - - 54

6. Bones of the arm, fore-arm, and carpus 55

7. The hand ----- 56

8. The thigh and leg of the fkeleton - 57

9. The foot of the fkeleton - 58

10. The adult fkeleton - 59
Figures of the mufcles.

11. A mufcular buflo - - - i 22

12. The fore view of a mufcular trunk - 123

13. The back view of the fame - - 124

14. Two mufcu'ar arms - - - 125

15. A mufcular arm and leg - - 126

16. Two mufcular legs - - - 127

17. A mufcular hand - - - - 128

Figures

I N D E X, 34*

Page

Figures of the mufcles.

1 8. A mufcular foot - 129

19. A complete mufcular figure - - 130

20. The mufcular figures of Hercules and An-

taus - - - - - - 131

Figures of the vifcera.

21. Vifcera of the abdomen and thorax infitu 249

22. The liver, pancreas, fpleen, and kidneys,

with the targe veffels of the abdomen, and
contents of the pelvis - 250

23. The lacleals of the jejunum "]
The origin and diftribution of the fupe- J" 251

rior mefenteric artery J

24. A full view of the vena port arum - 252

25. The vena hepatica 7
The biliary and pancreatic duels y ->

26. Receptaadum chyli et duclus thoracicus - 254

27. The fuperior and inferior cubital nerves }
Courfe and diflribution of humeral artery 3

28. The parts concerned in V. S. brachii ~) ^
A tumor extirpated from the cubital nerve 3

29. The medulla fpinalis ~)
The intercoltal nerve 3

30. The animalcules infemine \
The circulation in a fifh's tail \ -
A fmall artery and a vein fpread on a f ->

membrane J

Figures of the organs of generation.

31. The bladder, with the proflate gland,")

veficula feminales, &c. i

A tranfverfe fection of the penis \ 3

A longitudinal fe&ion of the penis J

32. The female organs of generation - 313

33. The parts of two different hermaphrodites 314
Figures of the foetus.

34. The heart, with its large veffels ^
The heart, with the foramen ovale > 315
The venal fyftem of the liver j

Figures

H z

INDEX.

P«ge
Figures of the Eye, and Cafes of Surgery.

35. A diagram to illuftrate vifion, and the dark 7 ,

or infenfible point of the eye 3

36. The operation of imperforated iris

The operation for proptojis cornea J

A diagram, whence dimneis of fight from )- 317

an opacity of the cornea
A diagram, whence the fenfe of light in

a cataractous eye

37. An ofTification in the dura mater
in the heart !

Two exfoliations of both tables of the [39
{cull ----- J

38. Wood, the miller - - - 321

39. The Bubonocele performed on Heyfnam 32a

40. White's exomphalos - - - 324
Fingers, bones of ----- 33
Fijlula in ano - - - - - 7 2 > x 57

perinao - - - - - 267

Flea, why numerous joints in its legs - 7

Fluids, their proportion to the folids - - 206

Foetus, it is nourished by the mouth - - 278

receives red blood from the mother - 182

circulation of its blood - - - 284

Foramen ovale - - - - - - .284

how clofed - - - - 287

not open in water-animals - 288

Fracture, how united by callus - 7

how bound up with a pafte - - 37

of the fcull - - - - 319

Funis umbilicalis - - - - - 283

Gall-bladder - - - - - - 163

Ganglion of nerves - - -. - - 227

Gland, what -_.__._ 3

■ ftruclure -. - - - 146

lacrymal - - - - - - 290

lymphatic - - - - - 212

miliary - - - - - - 136

mucilaginous, of joints - 47

Gland,

i8i

1 N* D E X. 345

Page

Gland, pineal - 213, 223

. pituitary 213, 222

* falivary - - - - - - 142

—————— economy - * - - 145

— — thymus - ' - - - - - 213

— thyroide - - - - - - 213

Glandula renales - - - - *> 263

Gonorrhoea - - - - - - 268'

Gutta ferena flate of the brain and optic nerves 225

Haemorrhage, why commonly on furfaces - 202

Haemorrhoides, how extirpated - - - 158

Hanging kills by interrupting refpiration - 176

Heart - - - - - - - 177

■ omfication of its mufcular fibres 5, 182, 319

, its bafis ulcerated, with pus in the pericar-

dium - - - - - - 181

1 large, lax, and filled with polypi in fatal

dropfies -

— its force - - - - - - 196

Jifiote anc * diq/i'ole 9 why reciprocal - 197

throws the blood along the whole arterial

fyftem ------ 200

Hernia. Vide Rupture.

aquofa - - - - - 264

Hydrocele - - - - - - 263

Hymen 273

. imperforated 273

Hypochondrium - - - - - l 34-

Hypogajlriwn 134-

Jaundice - - - - - - I0 °

Jaw, lower, not offified - 5

yejunum - - - • - * J 5°

Ileum intejiinum - - - - - 1 5^

Iliac paffion - - - - - - I( ^ 3

Impofthumations, their feat - - - 139

Injection through the arteries into the veins 203

Inteftines *SS— l S%

— why fuch a length of - - 156

Joint

344 I N D E. X.

Page

Joint of the thigh impofthumated - - 29

. difeafes of 48

Iris 2 9 r

- — ads as a fphincter mufcle - - - 292

Kidneys 2 95

, tubuli, papilla, glands, and pelvis - 260

, one frequently almoft confumed - 272

. fometimes but one - 272

Labia pudendi - - - - * ' 2 7 2

Labour, child-bearing, why at the ufual time 289

La&eals l68

Ligament, what 3

, where placed, and ufes - - 43> & c *

Ligamentum uteri rotundum - - - - 274

latum ----- 274

Lithotomy, an account of- - - - 3 2 5

Liver l6t

difeafed l6 5

dropfical - - - - - - 212

Lobfler, its fliells and joints - 7

Lungs - - - - - - - *7 2

Luxations of the fpine moft commonly at the

lower dorfal vertebras - 26
' Lymphaedudts - - - - -2,206

Males, why more born than females - - 275

Mamma - - - - - - - T 39

cancerous - - - - - x 4o

Marrow, oily ------ 5^

bloody 5

« cells, veficles, &c. - 6

Maxillary gland - - - - 143

fchirrhous proving fatal in nine

weeks - - - - *43

Mediajlinum 1 7 2

Medulla oblongata 224

wounded, caufes fudden death 224

fpinalis 224

Membrana

INDEX. 345

Page

Membrana oblongata, its wounds - - - 224

Membrana adipofa - - - - - 137

its difeafes - - " - 138

■ tympani. Vide Ear.

niclitans. Vide Eye.

Membrane, what 2,61

containing, inverting, &c. - - 141
Mefentery - - - - - . 160

Metacarpus - - - - - . 33

Metatarfus, bones of- - - - - 37

Miller, hiftory of the lofs of his arm - - 321
Mons Veneris - - - - - - 272

Mortification, mould feparate, before we amputate 208
Mufcles, what _---.„ 3

■ their fibres fuppofed veficular - - 62
1 rectilineal, penniform, ufe - 62, &c.

of the abdomen - - - - 6y

■ of the genitals and anus - 69
of the fcalp, ear, eye, lips, and nofe 72

■ ■ of the os hyoides, tongue, larynx, pha-

rinx, and uvula - - - - 78

of the lower jaw - - - - 82

- of the clavicula and fcapula - - 83

■ — of the os humeri - - - - 85

■ of the fore arm and hand - - 88
— — — — of the head and neck - 97

■ of refpiration, fpine, and pelvis - 102
■' of the thigh and leg - - - 108

■ ' of the foot and toes - - - 115

■ of the cjficula auditus - - Z°7-> 3°9
Nephrotomy, what panes for that operation 260
Nerves, what -.-'-.- 2, 225, 246

■ ganglions - - - - 227, 247
1 inftruments of fenfation and of motion 247

— whether vibrating cords or tradudory

tubes 228, 247

— feem to decuflate - - - - ,29*1

' the order of differing them - - 240.

of encepbalon and medulla fpinalis - *ao,

Y Nerves.

$ 4 6 INDEX.

Pags

Nerves, firil pair 230

fecond pair 231

- — probably decufTate - - 294

third pair 231

fourth - - - - - - 232

fifth 232

fixth 235

feventh 236

eighth 236

ninth - 238

tenth 238

of the medulla fpinalis - 240

firit cervical ----- 240

fecond ----- 241

third 241

fourth, fifth, fixth, and feventh cervical,

with the firft dorfal - 242

the twelve dorfal - 244

the five lumbar - 244

the facral - - - - 245

Nlcholls, Dr. his opinion of the fphenoidal finufes 14

Nymph a 272

Oefophagus - - - - - - I 5°

Omentum - - - - - - - *49

Os tinea 274

— athmoides - - - - - - *3

— coccygis '------ 22, 25

— femoris ------ 34

—frontis ------- 12

— humeri - - - - - - 3 1

— innominatum - - - - - - 28

— mala ------- 17

— maxilla inferior is - - - - - 20

fuperioris - - - - 18

— nafi 17

— occipkis - - - - - - *6

19

— „,.-•«-- 12

Os

INDEX. 347

Os pctrofum -___-.

— planum .._.-_

— facrum -----
— fphenoides

— fpongiofum -

— temporis ---.„-

— "comer -----._
OfJ'a etiquetra --_,...
OJJicula auditus - *
Offification in the */wnz wtf^r -

, , heart -

OiTifying matter, deficient in a lower jaw, and in

the rickets - - - - -

Ovaria -------

Pancreas -------

Paracentejts _>_.._

Parotis, gland _-.-„-

- its duel: wounded -

ulcerated -

Patella -------

• how united when broken

Penis -------

Pericardium - - - - - - 177

containing pus - - - 1 8 1

adhering to the heart - - 181

Pericranium - - - % - 10

Periojlamm - - - - - - 10

thickened in rickets - - 5

Peritonaeum - - - - - - 148

Pia mater - - ~ - - - 221

. oflified - 221

Placenta - - - - - - - 281

its vefTels anaftomofe with thofe of the

uterus - - - - - 282

Pleura - - - ' - - - 172

Pleuritic pains, why more commonly in the left fide 1 78
Polypus of blood - - - - - 210

Pope's eye in brutes - - ■ - - - 214

Procefjus

Pajre

J 5

1 8

2, 25

J S

20

l 5

. 20

8, M

3°7

3*9

-
5

274

165

1 1 1

l - 2

M3

143

35

35

34 8 INDEX.

Page

Procefus ciliares - - - - - " 2 9 2

Procidentia ani - - - - * 1 57

Projiata 2 ™

difeafed 266

Papilla 2 9 l

how contracted and opened - _ - 292

why round and oval in different animals 292

Radius 3 2

Receptaculwn cbyli z °°

Reclum intejlinum I 57

Regio umbilicalis - - - - * " J 33
Refpiration, motions - 104, &c.

ufe l 73

Reticulum muccfum - - - - • *35

Retina 2 93

Ribs, fractured or diftorted by carelefs nurfes 27
Rupture of matter, and probably of the gut, un-
der Fallopius's ligament - - 47

of matter, and of blood and matter into

the fore part of the thigh - - 19°

of water ,'-•-'- 264

cafe of Hey/ham - - - - 3 22

, White 3 2 4

Sanguification - - - - - - 2I 7

Sclerotis tunica oculi - - - - - 2 9*

Scapula ------- 27

Scarifications, when hurtful ... 208

Scrobiculis cordis - - - - - - x 33

Scurvy, how affe&s the cuticula - - - 134
Scull. Vide Cranium,

fradured 3 X 9

Secretion, how performed - - - - 147

Seed, the nature of its animalcules - - • 269

Sella turcica - - - - - " *3

Sinus , frontal - - -'- - - J 3

of the os fphenoides - - - - 14

of the maxillary bone - - - 19

fometimes impofthumated 19

Skin

INDEX. 349

Page

Skin ------- 135

Smelling, the fenfe of . - - - * 3*°

Solids, their proportion to fluids - 206

Spine, bones of 2l

- why compofed of fo many bones - - 22

final caufes of its different curvatures - 23

Spleen l6 7

Sternum -------

Stomach I 5 I

Stones, extra&ed from the loins - - - 260

Stone, fymptoms of, equivocal - - - 261

- account of the operation - - - 325

Sublingual gland *43

Suppreffion of urine, in the kidneys and in the

bladder, different 262

_ _ how to be treated - 262

Sutures, how formed

.what 3 11

. particular ones - - - - 3 I l

Tapping for the dropfy - - * 2I *

Tar/us, bones of - 3"

Tailing, the fenfe of 3 11

Teeth 2 °

{bed 2I

Tendons, what - 3

pricked in bleeding - %9

Tefes - 26 3

Thymus, gland - - . . - - * 2I 3

Tonftlla glanduU - *44

how extirpated - J 44

Tooth-ache, its feat 2I

Trepan, not applicable at the frontal finus - 13

Tuba Fallopiana - - * . ." 2 75
Tumors, fmall ones under the fkin giving ex-

quifite pain -
Vagina -

Vafa defer entia -
Vein, what

136

*73
266

Vein

35° INDEX.

Page

Vein coats - » - . - 194, 205

why curved in its courfe - - - 104

why cutaneous on the arm - - - 102

cava, with its branches - - - 191

cephalic, how avoided in cutting irTues - 192

port arum - - - - - - jq?

in the fcetus - - - - 2 8' v

■ — -pulmonary - - - - 183

Vena latlea - -. ._ _ j^g

Vertebra ' - - - - - . 21

their claffes - - - - _ 2 2

bodies, procefTes - - 23

fupeniumerary - - - - 28

Veficula Jeminales - - - _ - 2 66

Vifion, the retina ^ the organ of 294

caufed by an impulfe on the retina - 297

how carried on after couching - - 298

' why do objects appear ilngle - - 295

why do not objects appear inverted - 297

observations from a young gentleman,

who never faw till couched - - 300

Vitreous humour - - _ - - • 2 oo

Ulna ---_-__ qi

Ureters - - - -"•'.- - - 260

• diftended in calculous patients - - 271

Urethra ------- 268

its glands 268

ftrictures - 268

in women

273

Urine pafles only by the ureters - - - 262

Uterus - - - - _ _ _ 273

White fweiling ---->_ .5

FINIS.

MEDICAL LIBRARY

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